Just trying to see what's involved here, cost-wise, and hurdles.

I found a 40hr used Fast XFI system for a BBC, guy wants 2500.00. This is a 4000.00 system. Need a distrib though, and the one that was suppose to come with the kit is like 350.00. He has a pair off a boat actually. Otherwise the system is complete, less fuel lines. Good deal?

Other options are the Holley 950, and although not a good comparision, the new EZ-EFI system from Fast. Lot cheaper, and probably will do what I want. Tech support is very important, gotta be able to talk to somebody. Biggest fear is dropping all this money, and the car dont run as good as it did with the carb!

Also, forgive me for being overly simplistic. As far as tuning one of these systems, cant you just creat a target idle of say 14:1, cruise 14-14.5:1, and WOT/high load 12.8:1, and be done with the tuning? I realize there's start-up tuning to do also. Hell, what if you just made everything 13:1? That will work all around, although a bit rich for cruising admittedly.

Check Big Stuff 3. It was built by the guy that opened FAST and is supposed to be the cat's meow. I'd avoid Accel (the RamJet injection setup is a joke).
Call Tracy at Sunset Racecraft, he has logged a lot of hours with the FAST stuff. (806) 747-2700.

That is a good price if all components are clean and good.
Should be able to get a special harness to go straight to any dist. if not running a crank trigger.
I run the fast xfi on a 640hp 468 with a 109cl cam.
My car does not run as good as did with carb. I have not taken to dyno to tune though.I only have 9.5" on vac. at idle.
No such thing as set and go tuning.
My car does run better with a crank trigger and sequential fuel instead of bank to bank.
Changing fuel,timing is so easy though..just key strokes. No more jets or dist. wrenches needed.
Changes are easy to make,but when your on the floor with a big block...you are to busy to play with a laptop and drive :)
Must go to chassis dyno.

I did a megasquirt system for about $1600. you just have to patiently wait for the parts to show up used, eg, I sold the ported manifold(holley) fuel rails, and 8 used injectors,on ebay for $200 new they cost about $800 combined.
dont pay more than 300 for a used 1000cfm 4brrl throttle body.
if you need small injectors you can get them for $100(30lb per hour)

you can set a target afr and the computer can try to put it there but its not ideal.far from ideal you want to have a pretty good table, then maybe the computer can have 15% control. they say +-3% control is good. I know many guys who run 100% off their table.

with megasquirt, the software actually creates a pretty darn good starting table for you when you give it CID, injector size, desired AFR,etc. mine was dead on at 13.5:1 afr at idle.
with a friend and a good laptop, you can dial in your tune 90% of the way
with EFI, my car idled a lot better,had more vacuum, and the throttle response was better

dont get the holley system, or the EZ efi.

two things. try to be watching your AFR through the software that comes with the gauge the first time. analog gauges have been known to be off. also have full exhaust on the car as open headers can sometimes provide a false lean reading

I just checked the FAST website and the master kit was $2244 new.
http://www.compperformancegroupstores.com/store/merchant.mvc?Screen=CTGY&Store_Code=FS&Category_Code=EFISystemEZIEFIKits

Check with DougF here on the Forum. He can point you the right way. He has a killer EFI setup on his mid 9 sec 491" Tunnel Ram Nova that starts and idles and drives very sweet!


JIM

Interesting thing about the Fast EZ-EFI is that it produced the same, or even a bit better power on some high HP motors. A ZZ572 620HP version made like 627HP. And Butler Performance (Pontiac folk) made the same ~550HP with the EZ-EFI as with an Holley HP carb. In fact, it made a couple of HP more. System can support over 600HP with the correct fuel pump. Price is right, that's for sure.

Vince,

FWIW, one of the cars that always fascinated me and got me motivated was Clarence Harding's 69 Chevelle SS. It is a EFI 502, and he can dial it in to run whatever. He was featured in Car Craft and Hot rod. It is full interior, power windows, locks, A/C, etc, and at the time of the publishing of the article, was running low 10's, and still had some work to do and 9's was not out of the question once it was dialed in.

HERE (http://www.carcraft.com/featuredvehicles/116_0111_1969_ss396_chevrolet_chevelle/index.html) is the Car Craft article.

HERE (http://www.hotrod.com/featuredvehicles/96760_1969_chevelle_ss_396/index.html) is the Hot Rod article.

http://image.hotrod.com/f/9517915+w750+st0/p176812_large+1969_chevrolet_chevelle_ss_396_coupe +front_right.jpg

http://image.carcraft.com/f/9574863+w750+st0/116_0111_ldcz+1969_Chevrolet_Chevelle_SS396+passen ger_front_side_view.jpg

http://image.carcraft.com/f/9574875+w750+st0/116_0111_gcz+1969_Chevrolet_Chevelle_SS396+engine_ bay_view.jpg

http://image.carcraft.com/f/9574893+w750+st0/116_0111_cchz+1969_Chevrolet_Chevelle_SS396+engine _bay_view.jpg

Vince,I have been looking at the fast ez efi also, there are some threads on efi over at team camaro

Here is the newest one - Powerjection III

http://www.professional-products.com/new.html

I've run the first Gen FAST EFI for close to 10 years now. heir tech support was not that good and the design of the stuff was less than great for the after market. I could easily blow the computer due to a bad fan relay. The driver was an unprotected open collector transistor. 50 bucks plus shipping to fix it. All because they used a 5 cent part instead of a 30 cent part.

Over all it works very well though. High rise manifold yet it will start and run no problem at 10 below. Try that with a Carb.

The software is good. As a number of people mentioned before you need a good chassis dyno.

I strongly support EFI, and the number of units available now is incredible. If you were really serious you would get a MOTEC. Big Stuff is probably better than FAST at this point.

Ron

Vince,
Check out what Holley will release at SEMA in a month.

Vince,
Check out what Holley will release at SEMA in a month.

Can we talk about this now?

Andrew

Vince,
Check out what Holley will release at SEMA in a month.


Come on Doug - your killing me! How about a slight,and I mean slight, hint?

Well, the way EFI systems go, they are very technology and feature based, so inherently each time a new system comes out, it (should) one-up what else is out there with features and technology. You take a look at the competitors strengths and weaknesses, and work to improve in those areas. I know that is just rambling, but anyhow.

I'll give you some slight hints. :) Some of these probably don't interest your application, some will.

Most EFI systems don't currently address running "late model engines and their features". This will.

Several systems boast "self tuning" features, that is not a simple term and can mean a lot of different things, but to come out with a new system that doesn't offer features regarding that, would be silly. No need to have to keep pecking at a keyboard to tune a fuel table. Makes it a lot easier for not only the novice, but saves time for a professional.

And there will be a bunch of cool add-ons other people don't offer.


That is just a couple of small comments.

For your application (big cam and a 5sp), I would highly recommend a laptop tunable system and not one that doesn't allow you fine tune certain areas. Some systems mentioned don't allow you to tune about anything, and if it isn't right, you are pretty much done.

Thanks Doug. I need to make a descision on this cam, as its *slightly* to big under 2000, and its mostly due to induction. Confident that EFI would smooth this out immensly...not that it's too bad to begin with though.

EFI SHOULD help, but doesn't guarentee completely. The intake manifold design has more to do with it really. A single plane EFI intake will have "reversion" and "cross talk" between the cylinders. An intake that has a big plenum that "seperates" the runners from each other helps more (like an LSx engine, or to the extreme, and independent runner intake).

You just end up having to run it a little richer to help "cover up" the lean cylinders.

Bumping up the LSA really does help those issues, vs lowering the overall duration. Lowering duration defintately loses higher RPM power. Upping LSA, from all the dyno testing I've done hardly affects power at ANY RPM (within reason). I've never seen the big power differences I've seen quoted here and there.

Don't get me wrong, EFI can really help those issues, the timing control alone is a big help and getting the precise amount for every operating point (while not affecting other points like you do with a carb) helps a lot.

Thanks Doug, very helpful. I was thinking the same cam that I have on a 114 vs the 110 may be all I need, but hate to go through the trouble of a cam swap if it wasnt going to make a big difference. I have a Weiand Stealth dual plane right now, which comes with the divider cut way down. Motor really wants a single plane, but cant get one under the hood. Nice to know that the intake I have may be reducing the reversion. Maybe an RPM intake with its almost completely intact divider would help further. Other option is reducing duration to the low 230's, as I know that's smooth. Just afraid it will kill power though.

Maybe an RPM intake with its almost completely intact divider would help further. Other option is reducing duration to the low 230's, as I know that's smooth. Just afraid it will kill power though.

Vince,

Yes, and yes....

Having the dual plane intake with the divider only notched 1" will help tremendously, if you want to stick with that cam.

If I were in your shoes, and I have had said this before, I would go with my cam, the Voodoo 60234, but on a 112 lsa, keep the Stealth intake, for your combo. You will have the best of both worlds, and not loose too much on top due to keeping the Stealth intake. If you feel that may not be enough, opt for an RPM instead, but at some cost upstairs. I had crisp, responsive, throttle with that setup at that time, almost too much, and I am on a 110 lsa. The reason I push my cam on you with a 112lsa, is that you have slightly more cubes, AND my cam has more intensity from the adv as compared to the .050 numbers, which opens the valves faster, producing more torque and vacuum.

Something to ponder....

I have our new EFI system on a 502 right now. The cam I think is around 236@.050 (HR). Same intake as yours. It has a 900 CFM TBI on it. I am very surprised/impressed with how well it runs. You really can't tell it was TBI vs multiport. It definately thumps at idle, but drives super smooth. It has a 4L80E in it. Not as hard as your 5sp regarding lugging the enigne, but it is really smooth around 2000 and below. Of course I have it tuned decently, but didn't take anything crazy to tune.

I'm a proponent of port EFI (especially when running nitrous, etc), but this thing runs so nice, if it was mine, I'd leave the TBI on it probably.

Vince,

Here is what Harold said about the 60234 on a 502 BBC -
Cable,

Holley dyno-tested the 60234 against the Comp Cams 11-773-8 Xtreme Energy roller cam. Doug F. of this board may be able to give exact numbers, he was the dyno supervisor, but I seem to remember 654 about 6200, torque 640 ftlbs at 4500, 550 ftlbs at 2500. The 60234 beat the 11-773-8 easily.

UDHarold

Is 550lbs of torque at 2500 enough?

You can read that HERE (http://www.chevelles.com/forums/showpost.php?p=1157577&postcount=29). With the 112-114 lsa, that would drop down in the rpms quite a bit....

Great info guys. As far as Doug's experience with the new system...I would expect it to be smooth anyway with that *smaller* cam. My 454 was dead smooth down to 1200 rpms with a Voodoo 231/239 HR. I would expect in a 502 it would be smoother, even with a carb.

Walt, I dont think a 255/263 cam regardless of LSA is going to want to run at lower rpms. Remember, if you have a manual trans, it changes everything. I personally believe an auto car can get away with just about any cam. Stick cars transmit every missfire/roughness right to the drivers and passenger seats. No doubt that cam makes power. I just know how this motor "feels" and what its trying to tell me. The reality is, they way I drive it (rev from idle to 1800, then shift gears which drop rpms to ~1400), I really need a smaller cam. But HATE to give up the power that this cam currently makes.

Decisions decisions...

PS - I breifly tried a 1" open spacer on top of this dual plane, and she loved it! Too bad I didnt have the hood clearance for it. I didnt really notice any rougher running. Guess that rules out the intake.


Biggest difference in terms of driveability is carbs. My Prosystems which runs phenomenal, is the most tempermental and bucks/surges, shaking the whole car at low rpms. Any Holley off the shelf, runs smooth as silk, bringing everything to 95% perfection. But, they lack the response that the PS carb delivers. The HP Holley's run phenomenal also, but a bit too rich for my tastes. This is how I know that induction plays a large role here. Was thinking that EFI in one form or another could give me the best of both worlds.

You are right about the manual trans. An auto absorbs a whole lot of things a manual just transmits right through.

The benefits of EFI are as you mention, getting the tune how you want it, in each area. That is subject to how well the tuning is done. Not to say it again, but with the precision you are looking for, a laptop system would be what I'd be looking at. The non-laptop deal tunes are just too generic for what you want. You'll end up with a similar dilema that you have with the different carbs (liking some things and not other about each one), only possibly worse actually. Systems that don't allow for precision tuning generally have to default to a richer condition as that "covers up" things. Getting close to to lean, and crispness, is something you can't really do with a generic calibration, as it will be too lean for some applications.

Vince, well, I don't agree with you, but to each his own. You won't find out till you try it. But it almost sounds like your test and tune days are over with.

You could even take my suggestions a step further with an annular booster carb. I have a spare 850 Demon with annulars if you would like to try it.

Good luck and I hope you get it figured out.

Vince, well, I don't agree with you, but to each his own. You won't find out till you try it. But it almost sounds like your test and tune days are over with.

You could even take my suggestions a step further with an annular booster carb. I have a spare 850 Demon with annulars if you would like to try it.

Good luck and I hope you get it figured out.

Walt, I actually tried Joe's 800 annular, and it does drive excellent, no different than any other off the shelf carb. I may just run a standard 850DP, which does run excellent.

As far as cams, the Voodoo 60234 255/263 110* has 39* of overlap if I calculated it correctly. On a 114* it has 31* of overlap. My XR286 at 248/254 110 has 31* of overlap. The 231/239 110 HR I loved had 15*...hence the smoothness. Not sure how lash affects this calculation, but if you subtract lash from my cam, there's still 23* of overlap. Seems to me, going to a bigger duration cam and widening the centers nets the same result. I guess I can run an even bigger cam and not worsen the manners huh :D

You are right about the manual trans. An auto absorbs a whole lot of things a manual just transmits right through.

The benefits of EFI are as you mention, getting the tune how you want it, in each area. That is subject to how well the tuning is done. Not to say it again, but with the precision you are looking for, a laptop system would be what I'd be looking at. The non-laptop deal tunes are just too generic for what you want. You'll end up with a similar dilema that you have with the different carbs (liking some things and not other about each one), only possibly worse actually. Systems that don't allow for precision tuning generally have to default to a richer condition as that "covers up" things. Getting close to to lean, and crispness, is something you can't really do with a generic calibration, as it will be too lean for some applications.

Thanks Doug...I think if go EFI, your right, I need to get something fully adjustable.

Why does this REQUIRE dyno tuning? I mean, if you set the WOT ratio to ~13.1, it should be "there" in terms of max power right? I guess the low-speed/midrange/cruise is the PIA?

I don't think I said it requires dyno tuning anywhere. Assuming you are saying that as it is a "general comment".

You last sentence is somewhat of a common "misperception". You are inferring about "closed loop" control, meaning the ECU will automatically adjust the injection volume to meet a target A/F. While this is true, the fuel tables still need to be close for good drivability. ECU's are always looking at the base table and then using closed loop to adjust from there. If for example say the WOT fuel table, is too lean, and when you stab it and go to WOT, it will be lean for an instant until the closed loop "catches up". This is more of an issue at low RPM. The processor in the ECU can process this plenty fast, but you actually have a delay which is the overall feedback loop. Say you are lean and the ECU adds fuel, that fuel has to get to the 02 sensor and say I'm lean, then add more fuel, by that time (at lower RPM mostly) conditions ahve changed. So you need the fuel table to be "close". If they aren't, transient conditions will suffer.
Hence the need for "tuning" to minimize what closed loop does.

However, you might say, "can't the ECU do this tuning for me"?

Maybe it can... ;)

As far as dynos, from my experience, you certainly don't need a chassis dyno to tune (arguably they are best to find problems which most people end up having, fuel pressure drop, etc). Get it dialed in so the base tables are close and you are pretty good, don't really need the dyno. The dragstrip is the best dyno, period. The ET slip tells me what I need (IMO and experience).

People can go nuts on an eddy current chassis dyno fine tuning part throttle spark for best power, etc, but in my experience, 10% of the effort results on 90% of the results. Heck, I tuned my Nova for probably 10 minutes.

The main thing you have to know (which most don't) is "basic tuning". If you can tune a carb (understand jets and bleeds, etc), EFI will be simple! Really.

Thanks Doug, I have a much better understanding of what's involved as far as tuning goes. I kinda wanna try this...

How about an EFI 101 sticky? You seem to know alot, and know how to explain it!


Thanks again Doug,
Vince

megalogviewer-which is free and works with datalogs from megasquirt,

will actually take your datalog, look at your ve and afr tables, look at your pulsewidth,afr etc from the log, and actually suggest a table for you based on your target afr.

pretty darn slick -you can set the rpm range and map range you want to tune for or you can tune the whole table. of course, the bigger the log you have the better the results you'll get

Thanks Doug, I have a much better understanding of what's involved as far as tuning goes. I kinda wanna try this...

How about an EFI 101 sticky? You seem to know alot, and know how to explain it!


Thanks again Doug,
Vince


If the Mods wanted to do it, I'd start rambling on for a bit.

I'll second the vote for the EFI sticky.

I'll second the vote for the EFI sticky.

actually maybe a (Forum under specialty) like team camaro has??



Threads in Forum : EFI in your modern Classic

http://www.camaros.net/forums/forumdisplay.php?f=70

If the Mods wanted to do it, I'd start rambling on for a bit.


I am THOROUGHLY enjoying your rambling. Please continue.

:thumbsup::hurray:

I paid full price for the kit and think it's pretty good. Missing a few minor things but for that price seems reasonable.

This is starting to get fun!!


JIM

As far as dynos, from my experience, you certainly don't need a chassis dyno to tune (arguably they are best to find problems which most people end up having, fuel pressure drop, etc). Get it dialed in so the base tables are close and you are pretty good, don't really need the dyno. The dragstrip is the best dyno, period. The ET slip tells me what I need (IMO and experience).

People can go nuts on an eddy current chassis dyno fine tuning part throttle spark for best power, etc, but in my experience, 10% of the effort results on 90% of the results. Heck, I tuned my Nova for probably 10 minutes.

The main thing you have to know (which most don't) is "basic tuning". If you can tune a carb (understand jets and bleeds, etc), EFI will be simple! Really.

In my experience (which is to make my car a daily driver as well as a track car) you can't get drivability over temperature and altitude without a good chassis dyno (not a drum type but an eddy current or hydraulic dyno where rpm can be held constant over load).

Software is key also, I'm surprised this hasn't come up more. Accel has password protection on their systems (as of a year ago anyway) and you had to be a "certified dealer" to get to the point that you could make needed adjustment.

Data recording is also needed as part of the software. Test drives with the data recorded help tremendously with tracking down drivability problems.

Ron

I am about to be a FAST XFI user. Have the stuff sitting in a box at home.

I went EFI because of turbo usage and the term "fast idle" sounds so much cooler than "choke". :D

I will be using a Holley 4125 intake (ready for EFI) and probably an intake elbow with a forward facing single large ~95cfm Throttle body.

In my experience (which is to make my car a daily driver as well as a track car) you can't get drivability over temperature and altitude without a good chassis dyno (not a drum type but an eddy current or hydraulic dyno where rpm can be held constant over load).

Software is key also, I'm surprised this hasn't come up more. Accel has password protection on their systems (as of a year ago anyway) and you had to be a "certified dealer" to get to the point that you could make needed adjustment.

Data recording is also needed as part of the software. Test drives with the data recorded help tremendously with tracking down drivability problems.

Ron

No doubt you can get a lot done quickly and over a large tuning portion with an eddy current chassis dyno. It's just been my experience that I can get a car tuned pretty well pretty quick without that being a requirement. Anytime I take a car off a chassis dyno and to a race track, the overall fuel curve usually needs a SMALL offset for best ET/MPH. Of course that pretty much depends on the air conditions in both places. I just don't think it is a "requirement". But yes, I'd rather be strapped to a chassis dyno rather than trying to tune a 600 RWHP car on the street.

I've seen people spend "hours and hours" tuning their EFI engines (and I'm not really sure what they are doing during that time?). Other than cold start, which you get one or two shots a day on, I can usually get something pretty well tuned in an hour or so. I'm not a 101% perfectionist. If the car "drives perfect", but maybe a datalog shows things that "don't look perfect" but are imperceptable other than the data, I don't get too hung up on that.

Just to show how crucial induction tuning is....


I just borrowed GRN69CHV's new 870 Avenger carb, and went for a drive. Damn thing runs so good, feels like I took 10* of cam duration out - really! I can pull in OD down to 1500 w/o bucking, and she's very smooth all around. Still has the typical 870 secondaries not coming in issue though. My Prosystems carb is alot more responsive, but doesnt drive as smooth as this. Big difference here folks.

Makes you wonder how much smoother still EFI would work here.

Doug, I should have been clear on the term "track". I meant a road race course not a drag course. I need throttle response at places other than full throttle. I also never had good luck with float bowls at high G's, they all leaked in one way or another. EFI fixes that too. Although it does move the problem to the fuel tank...

Which is another issue when you go to EFI, the fuel tank and delivery system.

Ron

Doug, I should have been clear on the term "track". I meant a road race course not a drag course. I need throttle response at places other than full throttle. I also never had good luck with float bowls at high G's, they all leaked in one way or another. EFI fixes that too. Although it does move the problem to the fuel tank...

Which is another issue when you go to EFI, the fuel tank and delivery system.

Ron

Ok.. Yea, a couple hours on an eddy current would be much quicker than having to tune a road race car on the track. :)

And you are right about the tank, especially when cornering with EFI. You'll know instantly if the pickup gets uncovered.

Whats the most plug and play EFI setup for a turbo or centrifigual blower? I'd like to run EFI but dont want to sit around messing with computers at all, thats what I do for work and I hate computers so you can see my issue. Does anything tune itself out of the box, especially for blow through applications? Couldnt a system be totally self tuning if it had an O2 sensor in each header tube or is the signal too slow to do it in a timely manner?

autronic and vipec has pretty nice autotune system

here is autronic autotuning

YouTube - Autotune on Mainline Dynolog

I was checking out the MegaSquirt systems. Here the carb to EFI kits. I would spend the extra couple of bucks to get the ECM put together. Your talking about 600-700.00. If you buy a used TB and intake with injectors, figure 1000.00??, fuel pump ~200.00. Were now at 2000.00 for a basically pieced together kit. Summit has the Commander 950's from around 2700-3100. Not sure if saving 700-1000 is worth the hassle. Anybody?
http://www.diyautotune.com/catalog/-c-53_69.html

Which is another issue when you go to EFI, the fuel tank and delivery system.

Ron,

Do you have a fuel cell or regular sumped tank?

Jason,

What is this green cylinder going into your tank?

http://imgcash5.imageshack.us/img401/7488/dscn0478g.th.jpg (http://profile.imageshack.us/user/peetsjunkie/images/detail/#401/dscn0478g.jpg)


What do the rest of you do to keep the pickup from being uncovered?

Ron,

Do you have a fuel cell or regular sumped tank?

Jason,

What is this green cylinder going into your tank?

http://imgcash5.imageshack.us/img401/7488/dscn0478g.th.jpg (http://profile.imageshack.us/user/peetsjunkie/images/detail/#401/dscn0478g.jpg)


What do the rest of you do to keep the pickup from being uncovered?

I have a regular sumped tank. A fuel cell wold be better but they take up most of the trunk. I get down to about half a tank on a track day before I have to fill up again.
On the flats I can run down to 1 gallon left in a 22 gallon tank though.

Ron

I was checking out the MegaSquirt systems. Here the carb to EFI kits. I would spend the extra couple of bucks to get the ECM put together. Your talking about 600-700.00. If you buy a used TB and intake with injectors, figure 1000.00??, fuel pump ~200.00. Were now at 2000.00 for a basically pieced together kit. Summit has the Commander 950's from around 2700-3100. Not sure if saving 700-1000 is worth the hassle. Anybody?
http://www.diyautotune.com/catalog/-c-53_69.html

The VE tables on the megasquirt are only 12 by 12 while on the FAST they are 16 by 17. Much better control over the RPM MAP range. A lot less money though.

The Holley is 16 x 16.

Ron

Ron,

Do you have a fuel cell or regular sumped tank?

Jason,
What is this green cylinder going into your tank?

http://imgcash5.imageshack.us/img401/7488/dscn0478g.th.jpg (http://profile.imageshack.us/user/peetsjunkie/images/detail/#401/dscn0478g.jpg)

What do the rest of you do to keep the pickup from being uncovered?

That is my homebrewed surge tank. I just finalized the design last night. It's been in design now for a few months. I didn't want to spend $100 on a nice aluminum tank only to hack it apart. This was an REI water bottle that will drop into the tank and act as the surge tank, $2.

I wanted to make sure the design was all self contained. The basic design is having 3 fittings on the top of the tank. One to fuel rails, one return from rails, and a pressure feed for the jet pump. The jet pump is just a -6 to 3/8" line that splits off the back of the pump. (I have the A1000 so I should have enough excess to spare) This goes back into the tank into a brass tee that will fit underneath the cup.

Then I tapped and drilled a 1/8" plug in the tee to create the venturi to pull the fuel from the bottom of the tank and spray it back into the cup. This is what feeds fuel to the cup from the bottom of the tank. I used another 1/8" piece of threaded pipe to feed back into the bottom of the cup. Also the return will fill the bucket up providing constant flow.

Hoping to get a final pic of it tonight with all the parts I used.

I was checking out the MegaSquirt systems. Here the carb to EFI kits. I would spend the extra couple of bucks to get the ECM put together. Your talking about 600-700.00. If you buy a used TB and intake with injectors, figure 1000.00??, fuel pump ~200.00. Were now at 2000.00 for a basically pieced together kit. Summit has the Commander 950's from around 2700-3100. Not sure if saving 700-1000 is worth the hassle. Anybody?
http://www.diyautotune.com/catalog/-c-53_69.html

Fully assembled ms is $400.youull spend $100 on relayboard and wirebundle. You'll spend $10 at the jy on sensors and connectors.

New intakes are 220 on ebay. Tbs sell for 300 all the time on the used market. Injectors sell for 200 give or take. You would save $1500 over a holley system and have more control

Fully assembled ms is $400.youull spend $100 on relayboard and wirebundle. You'll spend $10 at the jy on sensors and connectors.

New intakes are 220 on ebay. Tbs sell for 300 all the time on the used market. Injectors sell for 200 give or take. You would save $1500 over a holley system and have more control


What about the fuel rails and associated machining, and fuel pump? Probably wont hit the JY for the sensors to be quite honest.

The VE tables on the megasquirt are only 12 by 12 while on the FAST they are 16 by 17. Much better control over the RPM MAP range. A lot less money though.

The Holley is 16 x 16.

Ron

this has not been correct in years. Megasquirt II has 16x16 tables for everything. most people still use the 12x12 because they are accurate enough for 99% of people out there, but the 16x16 tables are there if you want to use them

What about the fuel rails and associated machining, and fuel pump? Probably wont hit the JY for the sensors to be quite honest.

as I said, in my case I sold my bbc intake, fuel rails, AND injectors for $200. they are cheap on the used market. check ebay. I think new rails are like $100. I know I just bought new rails for my ls1 vic jr and they were $80

I bought new sensors($40 for the iat and clt) and I picked up used ones from the jy. I tested them all and the 15year old ones are still perfectly good. matter of fact, megasquirt lets you calibrate your tps so I calibrated the jy tps and sent the new one back to summit for a $30 refund.

thats another thing to research. do these other systems let you calibrate your tps? your AFR sensor values etc?

the megasquirt deal is very flexible and the programming is all open source.

I'm more and more interested in megasquirt instead of paying $1000s to people who do stuff like limiting access to dealers only and other cruddy deals like that.

as I said, in my case I sold my bbc intake, fuel rails, AND injectors for $200. they are cheap on the used market. check ebay. I think new rails are like $100. I know I just bought new rails for my ls1 vic jr and they were $80

I bought new sensors($40 for the iat and clt) and I picked up used ones from the jy. I tested them all and the 15year old ones are still perfectly good. matter of fact, megasquirt lets you calibrate your tps so I calibrated the jy tps and sent the new one back to summit for a $30 refund.

thats another thing to research. do these other systems let you calibrate your tps? your AFR sensor values etc?

Do you think that a novice would be able to put together a MegaSquirt system without pulling their hair out? Seems like a MS is more for the seasoned EFI people.

That is my homebrewed surge tank. I just finalized the design last night. It's been in design now for a few months. I didn't want to spend $100 on a nice aluminum tank only to hack it apart. This was an REI water bottle that will drop into the tank and act as the surge tank, $2.

I wanted to make sure the design was all self contained. The basic design is having 3 fittings on the top of the tank. One to fuel rails, one return from rails, and a pressure feed for the jet pump. The jet pump is just a -6 to 3/8" line that splits off the back of the pump. (I have the A1000 so I should have enough excess to spare) This goes back into the tank into a brass tee that will fit underneath the cup.

Then I tapped and drilled a 1/8" plug in the tee to create the venturi to pull the fuel from the bottom of the tank and spray it back into the cup. This is what feeds fuel to the cup from the bottom of the tank. I used another 1/8" piece of threaded pipe to feed back into the bottom of the cup. Also the return will fill the bucket up providing constant flow.

Hoping to get a final pic of it tonight with all the parts I used.

Pictures would be nice because you kind of lost me there. Are you dumping the return fuel from the rails into the cup also? Is a jet pump another low pressure pump? And while I'm asking what the heck is an A1000, a high pressure pump? I actually think I saw your surge tank in the camping isle in Wal-mart today!

Sorry for being thick. I guess that's why have reservations about MegaSquirt.

Mark

Do you think that a novice would be able to put together a MegaSquirt system without pulling their hair out? Seems like a MS is more for the seasoned EFI people.

It was my first time and it was dead easy. the diyautotune wire bundle is labeled every two inches and uses the same color codes as original gm wires so its hard to go wrong. there really is nothing to it.

whats even better is that tunerstudio will suggest a starting table for you and in my case it was very close. you'll be able to start and idle the car with the suggested table and then just tweak from there. no pulling hair at all.

a1000 pump is a nice pump that a lot of turbo guys use. they say it can handle 1000hp.

a lot of guys also use cheaper/quieter pumps when the power level is less. Im using a plastic fuel cell for my tank - you can use ANY tank or cell for efi.

Pictures would be nice because you kind of lost me there. Are you dumping the return fuel from the rails into the cup also? Is a jet pump another low pressure pump? And while I'm asking what the heck is an A1000, a high pressure pump? I actually think I saw your surge tank in the camping isle in Wal-mart today!

Sorry for being thick. I guess that's why have reservations about MegaSquirt.

Mark

Return dumps inside cup

Jet pump is fed from the output of the pump, basically a tee after the pump to force fuel back into the tank into what people call a "jet venturi". My pump should be able to feed both the rails and the jet circuit.

A1000 is pump that comes with the FAST EFI kit.

I'm learning from all the other smart guys on here about this stuff too :) If you have lots of time on your hands, MegaSquirt looks cool. If you have wife, kids, and no time, FAST EFI it is for me. Might not be the best, but it seems to be popular.

Just to show how crucial induction tuning is....


I just borrowed GRN69CHV's new 870 Avenger carb, and went for a drive. Damn thing runs so good, feels like I took 10* of cam duration out - really! I can pull in OD down to 1500 w/o bucking, and she's very smooth all around. Still has the typical 870 secondaries not coming in issue though. My Prosystems carb is alot more responsive, but doesnt drive as smooth as this. Big difference here folks.

Makes you wonder how much smoother still EFI would work here.


Sure sounds easier and cheaper to have a carb for the street, and one for the track....

Sure sounds easier and cheaper to have a carb for the street, and one for the track....

No doubt EFI is not for everyone (from a cost and complexity standpoint). No doubt. But if you want some medium to big cam engine to run like a newer EFI car everytime you start it, as well as all the other benefits it offers, a carb just can't be made to run like that.

Regarding the laptop EFI system (any of them) - I always ask someone that is interested "Do you like tinkering/tuning your car?" If they say, no, I'd rather never lift the hood, then programmable EFI is not for you. If that is the case and you WANT EFI (and don't want to pay someone to tune it for you), then get a stock late model engine and ECU and stick it in.

The other big misconception is you need to be a "computer expert". If you can post on this board, you have the PC skills you need. The skill you DO need, which is becoming more of a lost art, if many people even had it at all, is basic ENGINE TUNING skills. Many people couldn't tell you if 12:1 A/F ratio is richer or leaner than 14:1. If that is the case and you aren't one that likes to learn, you will be frustrated. If you are a "good carb tuner" and understand what the bleeds and restrictions do, etc (and if you do you know more than me ;) ), then you'd love EFI. Much simpler than dealing with cut and try items on a carb, and change one thing on a carb and it messes up another. With EFI you can have the idle, driving, and WOT performance you want with no compromises.

If we start more posts I can comment some more on benefits of EFI when done right.

I'd like to think I'm half decent with a carb, and learned alot with my wideband tuner. I know exactly what this motor want in terms of AFR, and just cant get there (in all areas) with a carb, w/o messing up another area. I just need the price to come down a bit, doubt that will happen though.

Doug, just for now so I dont have to wait for the sticky ;) (hear that Mods??), can you let us know what size injectors are typically needed for different HP levels? And, do you size them according to dyno HP or installed HP? I'm around 600 installed.

this is one of many calculators online

http://www.witchhunter.com/injectorcalc1.php4

keep it around .5 bsfc and 80% max duty cycle. around 43.5 -55psi fuel pressure and it should come out with a number that should work

Doug, just for now so I dont have to wait for the sticky ;) (hear that Mods??), can you let us know what size injectors are typically needed for different HP levels? And, do you size them according to dyno HP or installed HP? I'm around 600 installed.

You size to actual engine (flywheel) HP. Too small and there is nothing you can do (other than raise fuel pressure) so you don't want to go there. Really the only problem of going too big is to get into a "non-linear" operating range of an injector which occurs at low opening times and when you get closed to full open (static conditions). That varies by each injector. If you have a sequential system (fires once every two revs) vs a batch (fires once every rev), you can get away with bigger injectors because it has to supply twice as much fuel each "squirt" since it fires half as much.

Anyhow, in the real world for you, a 600 HP BBC would like about a 42 lb/hr injector. A 36 would make it, but a 42 gives some room. And will idle just fine. When I say "big" I mean 100 lb/hr and up.

I run 60's in my 491 and can run a dry shot of nitrous. I'm probably around 800HP with the nitrous. Still have some room left then. Ran fine batch firing with a C950. Now I run sequential with my new stuff.

What about injector sizing for 1500HP and e85 fuel. :)

this has not been correct in years. Megasquirt II has 16x16 tables for everything. most people still use the 12x12 because they are accurate enough for 99% of people out there, but the 16x16 tables are there if you want to use them

Didn't know that 16x16 was an option. I stand corrected. The manual I had said 12x12.

I believe that 12x12 is way too small for a performance motor. It would of course depend on your expected dynamic range. A 700rpm to 6200 rpm motor would have a different need than a 600 rpm to 5000 rpm motor.

It just points out that there are a lot of things to consider in your choice of hardware and software.

Ron

No doubt EFI is not for everyone (from a cost and complexity standpoint). No doubt. But if you want some medium to big cam engine to run like a newer EFI car everytime you start it, as well as all the other benefits it offers, a carb just can't be made to run like that.

With EFI you can have the idle, driving, and WOT performance you want with no compromises.

I guess that is why I love working with the carbs, and getting the "rough idle" sound, of it not running "perfect". I can get it pretty close though. I like the idea of efi, but it takes away the nostalgia of owning a classic car. There is nothing better than looking at big shiny valve covers and a nice carb under a hood with a chrome air cleaner, just an old fashion clean look. Compare that with all the plumbing, wiring, etc. you have to see with the EFI setup. I can look at my new Mustang GT for that mess.

Another thing, as a Network Engineering Manager, managing and maintaining multi-million dollar networks, I like getting away from the "technical crap" and go back to some raw mechanical things. Just is nice and refreshing to going back and working on "old school" things. :thumbsup::beers:

I guess that is why I love working with the carbs, and getting the "rough idle" sound, of it not running "perfect". I can get it pretty close though. I like the idea of efi, but it takes away the nostalgia of owning a classic car. There is nothing better than looking at big shiny valve covers and a nice carb under a hood with a chrome air cleaner, just an old fashion clean look. Compare that with all the plumbing, wiring, etc. you have to see with the EFI setup. I can look at my new Mustang GT for that mess.

Another thing, as a Network Engineering Manager, managing and maintaining multi-million dollar networks, I like getting away from the "technical crap" and go back to some raw mechanical things. Just is nice and refreshing to going back and working on "old school" things. :thumbsup::beers:

I hear ya Walt. I like tinkering too, too much maybe, always in search of a better tune. Just imagine tinkering though w/o opening the hood and spilling gas, and seeing the results of your adjustment almost immdiately!

Doug, since your here :D, what are your thoughts on pieceing a system togther? I see alot of TB/intake/injector setups for sale used, w/various injector sizes. Does it pay to buy something like this if the price is right, then pick up a ECM and wiring harness? Are these things compatible for the most part? Personal experience, pieceing things togther usually does not end up saving me a whole lotta cash. But if I can save say 1000.00 - I'm all for it.

PS- difference bewteen bank-to-bank and seq, and is it something we should consider having?

I guess that is why I love working with the carbs, and getting the "rough idle" sound, of it not running "perfect". I can get it pretty close though. I like the idea of efi, but it takes away the nostalgia of owning a classic car. There is nothing better than looking at big shiny valve covers and a nice carb under a hood with a chrome air cleaner, just an old fashion clean look. Compare that with all the plumbing, wiring, etc. you have to see with the EFI setup. I can look at my new Mustang GT for that mess.

Another thing, as a Network Engineering Manager, managing and maintaining multi-million dollar networks, I like getting away from the "technical crap" and go back to some raw mechanical things. Just is nice and refreshing to going back and working on "old school" things. :thumbsup::beers:

Have you ever seen a picture of the engine in my Nova? Tunnel ram carb intake with port injectors and dual air valves. Old school/new school :). Hole in the hood with chrome air cleaners sticking out.

I hear ya Walt. I like tinkering too, too much maybe, always in search of a better tune. Just imagine tinkering though w/o opening the hood and spilling gas, and seeing the results of your adjustment almost immdiately!

Doug, since your here :D, what are your thoughts on pieceing a system togther? I see alot of TB/intake/injector setups for sale used, w/various injector sizes. Does it pay to buy something like this if the price is right, then pick up a ECM and wiring harness? Are these things compatible for the most part? Personal experience, pieceing things togther usually does not end up saving me a whole lotta cash. But if I can save say 1000.00 - I'm all for it.

PS- difference bewteen bank-to-bank and seq, and is it something we should consider having?

All my EFI systems were pieced together. I am poor :), and cheap, and have JB weld and a hacksaw...

My first EFI system I put on my Nova about 1993 had a Weiand X-celertor intake. I JB welded bungs in it. I took a Q-jet and shortened it and made it an air valve. I added a TPS to it and an IAC. Wasn't too pretty, but worked. Picked up about .1-.2 over the Performer and Q-jet I'd run for years.

My next was a 300-110 Holley I added bungs to on my old 388. I used a Holley TBI thottle body with the injectors removed for an air valve. The Holley 4bbl TBI is actually a very nice piece. Better designed than most of the fancy billet parts.

My 491 has a tunnel ram I added injectors in (actually had enough meat I didn't need bungs). Used a bridgeport and did it myself. Had a buddy tig the rail holddowns on it. Using 2 Holley TBI's for air valves again.

That being said, after using "nice" stuff at work here, I wouldn't cob things up too much. However, pretty much all the sensors are all GM stuff, and there isn't much compatibility issues amongst the parts.

So I'd have no issue "mixing" say a Holley manifold and rails with a FAST ECU. No issues at all. Just need the right connectors for the harness.

You do have to remember you have 45+ PSI of fuel pressure, don't want any leaks in the engine compartment....


Batch and seq - A few years ago I'd say it didn't make much of a difference except at idle where MAYBE seq would be a bit better. When I put the new EFI on my Nova this year, it has 2 WB02 sensors, I had a pretty big bank to bank A/F variance. When I switched over to sequential, it seemed to fix that a lot. I think it has to do with my plumbing and injector pulsations (there are odd things that can happen there people never know about, if you look at late model OEM engines, the rails have fuel dampers and are Engineered quite a bit), haven't had the time to look into it more. That being said, the car ran the same pretty much at the track. It just "improved what the data looked like".

The C950's are not seq and never saw that cause any "problems" directly in the last 10 years. Seq seems to be a pretty big "buzz" word, however, certainly doesn't hurt. You need a cam sync signal which is the only "downside".

You size to actual engine (flywheel) HP. Too small and there is nothing you can do (other than raise fuel pressure) so you don't want to go there. Really the only problem of going too big is to get into a "non-linear" operating range of an injector which occurs at low opening times and when you get closed to full open (static conditions). That varies by each injector. If you have a sequential system (fires once every two revs) vs a batch (fires once every rev), you can get away with bigger injectors because it has to supply twice as much fuel each "squirt" since it fires half as much.

Anyhow, in the real world for you, a 600 HP BBC would like about a 42 lb/hr injector. A 36 would make it, but a 42 gives some room. And will idle just fine. When I say "big" I mean 100 lb/hr and up.

I run 60's in my 491 and can run a dry shot of nitrous. I'm probably around 800HP with the nitrous. Still have some room left then. Ran fine batch firing with a C950. Now I run sequential with my new stuff.

this is great to know as I ran a set of 42lb units that I bought for $100 on the 468 and I am planning to run them on the turbod 5.3l to about 650hp. what kind of duty cycle were you seeing with the shot of nitrous and what was your base fuel pressure? Im planning to run about 57psi base fuel pressure with a 1:1 rise on the boost

this is great to know as I ran a set of 42lb units that I bought for $100 on the 468 and I am planning to run them on the turbod 5.3l to about 650hp. what kind of duty cycle were you seeing with the shot of nitrous and what was your base fuel pressure? Im planning to run about 57psi base fuel pressure with a 1:1 rise on the boost

74%. 43PSI or so. Not running high pressure. The car chassis dynoed 600 HP with a fair bit smaller jet. Not sure what it does with the .023 jets in it now.

71 Chevy, I looked again at the Mega squirt II manual and I didn't see anything about 16x16 map tables.

http://www.megamanual.com/ms2/

Can you direct me to where the 16x16 option is?

Ron

http://www.msextra.com/ms2extra/MS2-Extra_general.htm#features

"Explanation of the terms in the table

Fuel Table Size: The number of cells in the fuel tuning table. Note that because the rpm and load values are adjustable a good tuner is unlikely to need more than 12x12."

from a post on the MS forum:

"It would require code mods, but can be done (MS2/Extra has 16 x 16 tables as an option). The 12 x 12 is a fairly good compromise between resolution and wasting too much of the tuner's time. Talk with an experienced tuner about systems with 32 x 32 tables, and many of them will tell you that's so many they seldom bother tuning more than half the cells and just interpolate between the others. I've tuned a couple engines where I'm pretty sure I could have squeezed the 12 x 12 map I ended up with into an 8 x 8 without affecting anything."

There's some 2000cfm TB's with Dominator intakes out there...any reason NOT to run these on a 500-600hp motor? They are actually the same price as the 1000cfm stuff.

There's some 2000cfm TB's with Dominator intakes out there...any reason NOT to run these on a 500-600hp motor? They are actually the same price as the 1000cfm stuff.

It takes a smaller amount of throttle to let in the same amount of air, but I would personally do the dom tb andlive with the twitchy throttle. Also, I think they make progressive tbs in all sizes.

One thing to watch for is the tb arm. If its too long it won't allow a traditional air cleaner without some mods so pay attention to that

Thanks 71 chevy

There's some 2000cfm TB's with Dominator intakes out there...any reason NOT to run these on a 500-600hp motor? They are actually the same price as the 1000cfm stuff.

You'd DEFINATELY want progressive linkage. From a tuning standpoint, it doesn't matter as it can be tuned, but they can make some cars too responsive off idle.

Basically what will happen is say if your enigne actually needs 800 CFM of air, you will be at "WOT" at say 1/2-2/3 throttle. All the "feel" will occur between those 2 points.

What's the "range" of injector size that I can use? I know that 42lbs seems to be ideal. Anything wrong with 50lb'ers? How about 36? Car will probably be driven at 2000 rpms and below 99% of the time.

Doug, did you feel a real smoothing effect at low rpms with that SR cam and EFI? Not sure if you ever ran that motor with a carb for comparison.

What's the "range" of injector size that I can use? I know that 42lbs seems to be ideal. Anything wrong with 50lb'ers? How about 36? Car will probably be driven at 2000 rpms and below 99% of the time.

Doug, did you feel a real smoothing effect at low rpms with that SR cam and EFI? Not sure if you ever ran that motor with a carb for comparison.

36's should be ok, but will be close to maxed out depending on the real engine BSFC. I used to run 50's in mine. They would be fine in yours. So "36-50" would be the ideal range, but 36's would be on the short end possibly.

I've run that cam on the dyno with carbs, but that was pretty much WOT stuff.

People ask/tell me EFI "kills the cam", etc type comments. Removes the lope they like. From my experience, I don't think that is true at all. My engine thumps hard at 1000 RPM. I would say what EFI does, it lets it "thump" but not stall when put into gear, not hesitate, etc, etc. The EFI removes all the bad drivability traits you MIGHT have with a carb. There is a point where the "overlap cleans up" depending on cam and engine size, which is what I'd want to be the "mininum cruise point". I think that makes sense.

Granted mine is an auto with a converter, but I'd say mine "runs clean" around 1800. 1800 with a stick in OD, I couldn't say for sure.

The beauty of most EFI, is that you can fine tune each point, to a specific A/F ratio and timing that makes it the most happiest possible, without messing up other points. YOu just CAN'T get a carb to excatly what is best, everywhere, you usually have to go richer than you want in many places.

now, want to point out that Ive read/heard that really big cams still struggle with efi in the low rpms because the vacuum is all over the place, so much so that sometimes one has to use a speed density/alpha-n mix to smooth it out because the vacuum is all over the place for 100% speed density to be really effective.

doug?

now, want to point out that Ive read/heard that really big cams still struggle with efi in the low rpms because the vacuum is all over the place, so much so that sometimes one has to use a speed density/alpha-n mix to smooth it out because the vacuum is all over the place for 100% speed density to be really effective.

doug?

I've never really had that problem with a C950 or the new EFI.

I've idled at 6" of vacuum or less on some engines.

I have run Alpha-N on super comp type drag applications, but probably could run speed density.

I run speed density on all the stock eliminator cars I tune.

I'm sure the filtering and algorithms of a specific ECU matter, but I've never had to go alpha-n because speed density "didn't work".

You can add in vacuum dampers for idle with larger cams. There are references floating around the MS forums about a restriction and fuel filter in the MAP line.

With respect to batch/bank fire versus sequential... I suspect a lot here depends on the intake design and cam timing. A sequential injection pulse can be timed to hit when air is really moving into the port. Less reversion of fuel and thus mis-direction of fuel with short runner lengths this way. However if you have a longer runner and/or higher intake velocities then it likely does not make much difference.

The other consideration here is as RPMs go up and injector cycles extend, it is no longer possible to inject all of the fuel in the valve open time. Compare the effective duty cycle of the valve with the duty cycle of the injector. The injector spends a fair bit of time spraying on a closed valve.

With respect to table size limitations... one of the neat features of the MS is that you can specify the RPM and MAP points of each row/column in the table. Thus you can gather table cells around critical tuning areas and spread them apart where you spend less time. The code does interpolate between table cells to calculate values. By comparison many EFI computers only allow you to specify total range of the table and divide it up evenly across that range.

There is also a growing difference between the basic standard B&G MS and the MS-Extra firmware on the same hardware. There is a lot more current development occurring on the Extra firmware. And I would not even bother with MS-I anymore, I would consider MS-II the minimum.

I think you have to seperate some parts of the EFI system when you evaluate things to keep from confusing issues:

1. The EFI computer -- much of the usability comes from this portion. Could be a whole book comparing and contrasting and the target is constantly in motion. Basic spectrum is from the pre-tuned plug and play across to the complete laptop tuner models. One of the fundamental questions is how much do you want to learn?

2. The general injectors and sensors -- as this is so generic and standard they are almost not worth talking about. Go with GM and you are pretty good to go. Little bit of "engineering" required to get proper size on injector is about all.

3. The intake -- From a power and driveability perspective this is the most important element. IMHO there are way too many repurposed carb intakes and way too few EFI optimized intakes. When was the last time you saw an OEM EFI intake that looked *anything* like a carb intake? When was the last time you saw an aftermarket EFI BBC intake that looked *anything* like an OEM EFI intake? An intake optimized to EFI will take advantage of dry flow characteristics to seperate and tune the intake runners. It will also take advantage of not having to provide a centralized carb mounting pad and the compromises that brings. I would love to see someone build a good EFI cross ram for the BBC. Shoot Doug's comments about using JB Weld to attach bungs makes it sound almost doable at home... I have looked at a few intakes and pondered whacking off everything that is not the top of the engine or a port interface and then creating something using foam and fiberglass.

It will be interesting when I get around to installing it... I have an old Accel BBC intake that utilized a tunnel ram base with runner extension tubes inside an upper plenum chamber. They achieved a fairly long IR EFI setup this way. The main drawback is it sticks up too high (by about 1") for a stock hood. I'll either cut up a GoodMark cowl hood to fit or have to build a custom plenum box for it.

http://www.msextra.com/ms2extra/MS2-Extra_general.htm#features

"Explanation of the terms in the table

Fuel Table Size: The number of cells in the fuel tuning table. Note that because the rpm and load values are adjustable a good tuner is unlikely to need more than 12x12."

Thanks!

Ron

Note that the difference between 12x12 and 16x16 is MS-II vs. MS-II Extra. A few more goodies in the Extra version of the code.

I pointed it out before but worth highlighting is that with MS the user can configure what the RPM and MAP scale buckets are, gathering more control resolution where needed and reducing resolution where not needed. So 16 buckets is sufficient for 500 RPM per bucket/step from zero to 7000 RPM but you are not limited to that.

For example you could put buckets at 500, 700, and 1000 for fine control of fuel/spark around the startup and idle phases. Next buckets at 1500, 2000 because you don't run much there. Then run 2250, 2500, 2750, 3000, 3250, 3500, 3750, 4000 for micro-managing the mid-range off the corners. And finally 5000, 6000, 7000, 8000 for the top end where it may be consistently scalable. This is just an example, apply your own logic to the particulars :D

Note that you can do this bucket tweaking seperately on both fuel and spark control tables.