I'm considering upgrading my EFI system and looking for opinions as to which way to go. I'll give you my specs and history of what I have.

Engine specs:
* 496 cubic inch @ 9.75:1 CR (Somewhere between 575-620 hp)
* 049 heads w/ 2.19 intake & 1.88 exhaust valves (can only put rectagle port intake on the heads b/c of the porting)
* Hydraulic roller camshaft - 230/236 @ .547 lift both intake & exhaust - 112 LSA
* Long tubed headers
* Performance Distributors HEI distributor

4L80e and 3.73's behind it.

Any other details, please ask. I know the engine and what's in it, just thought this was enough to get information going.

The story:
I purchased a Throttle Body injection system when I had my 396 installed in the car. Not naming the company. I had (4) 62# injectors and it worked great. Now that I've upgraded to the 496, I upgraded to (4) 80# injectors. I knew that I would be on the edge of needing MPFI, but wanted to give my old system a shot. I'm having idle issues as the injectors may be putting out too much on the bottom end. When running the car anywhere above 1200 rpm, it's perfect, but anything below this is aweful. It has been quite a task trying to tune this bad boy and it's still not quite right by far. I want to get it dynoed, but with the issues I'm having, I'd rather upgrade and sell my old system. This is why the estimate of horsepower is somewhere between 575-620.

So, I'm looking to savage as many pieces as I can from my current setup. Like keeping the distributor and fuel system and any other pieces. I'm sure all systems come with it, but definitely has to have a TPS for my 4L80e controller. Looking for something also to place a round air cleaner on top to keep it somewhat old school looking. And must be a rectangle port intake manifold.

Suggestions please,

Well, I'm running the FAST EZ set up on two cars and like it alot. You could just buy the basic system that doesn't include the fuel pump and fuel lines but you will need a fuel system that provides at least 43 psi. I like the self learning feature and the adjustability it gives you. While I can't speak to the Holley systems, from what I've read they seem to be pretty good too. The EZ EFI is stand alone from the ignition so you wont have to change distributors but a MSD 6AL is best for the tach signal.

There are likely many systems that could work for you...

Point I want to make though is with regards to your distributor setup. You *can* run just the fuel via EFI (this is what it sounds like you have been doing?). But, apart from dividing the tuning process, why would you want to? Most of the current generation of EFI systems are designed to control spark as well as fuel. And the tuning capabilities are a huge step up from what you can do with an old school vacuum/mechanical distributor.

Let me give you a case in point... I run a 396 with a carb and HEI. Probably about 10.5:1. A decent hydraulic roller cam with 236/242 @ 050 and 610 lift. On a good day it idles at 12" of vacuum with a best case setup on the HEI. That best case is 18* of initial, which is generally the max before hitting high cylinder pressure before TDC at cranking RPMs on a Chevy motor, with 12* of vacuum advance all in at 9" hooked up to manifold vacuum. So I am idling at about 30* of advance... but could use more. An expirement with another Chevy engine showed idle continued to improve as initial was increased up to 36-38*. You just cannot get there without having too much total advance with a basic vacuum/mechanical advance ignition system.

You can get there with a computer mapped EFI ignition system though ;)

With computer mapping you can ratchet timing advance up and down with where the engine comes on the cam and cylinder pressures and mixture stabilization optimizes.

Steve,

Thanks for the reply. I'm open to any suggestion, which includes changing out the complete fuel system including the distributor. If possible, I'd like to savage as much as I could. When I converted to EFI a few years back, I thought it was the greatest thing alive, even though I knew nothing about it. My experience before the EFI system was to set timing using a timing light and set a Holley carb using a screwdriver. I knew nothing about meters and knew nothing about AFR. I tinkered around reading a few things here and there and learned just very basic information which included AFR and a couple other properties. Recently, I've been digging around and learning much much much more about things that I've never heard of. I'm slowly learning about it, but it's still mostly greek at the moment.

I realize my engine setup is on the edge of needing something more than just a throttle body setup with (4) injectors. The MPFI seems to be what I need, but I'm still stuck with having to learn about all of these different properties that I still don't know what it all means.

I have checked out Mass Flo EFI, which seems to be a preprogrammed computer. This sounds great for the meantime, but as I learn more, I want to be able to dig a little more and do more customizing.

So, yes currently I do run an EFI system that is separate from the Distributor. Through recent studying, it seems like there are systems that are 10 fold better than the one I have and of course they include a distributor in it's kit.

I read through Vince's Holley Avenger MPFI posting and it seems like his system is a Distributor separate system as well. I guess I just don't understand enough and sometimes want to revert back to a carburetor, but I would feel defeated and probably wouldn't be as happy.

You are pushing the limits HP wise with a single TB set up. You could go with a dual quad set up like I did with my 406 (not necessarily with a tunnel ram) which is good for 1000 hp. A completely programable EFI like the FAST XFI might do you better. I might upgrade to a XFI set up on my Camaro as the EZ components are compatible and I have this urge to turbo charge the dam thing.

To be quite honest with you, I'd love to get my current system to work with my engine setup. This would eliminate needing another newer system completely. But as I can't quite figure the system out, I"m thinking about something much more user friendly. Dual Throttle bodies would screw me up twice as bad.

If I could sit down with someone or having someone explain what I'm really looking at, it would probably help and I could probably actually do something with any system.

I'll probably call all of the different vendors and squeeze as much information as I can out of them. The only thing I'm afraid of is that each vendor will swear that their product is better than the next guy for whatever reason. I guess I just hate not knowing and being taken advantage of. A dual setup is definitely not my 1st option.

ya, the tunnel ram is a little on the extreme side. Most of the self learning systems use engine vacuum as a load signal and that with TPS position, coolant temp and air intake temp and RPM sets it fuel map. You want 8" of vacuum at idle as a mim. My 406 is borderline but a 496 putting out 600 or so hp should do better, but in any case your pushing the limit with the EZ. Depending on who you talk to what what you read it a 600-650 hp system.

Does anyone here use the Mass Flo EFI system?

I've been reading up on it a little and it seems interesting and comes with the distributor to tune along with the ECM. It is a MPFI system that uses (8) injectors. It seems pretty straight forward, but looks like it doesn't allow for additional tuning.

I'll call a couple of the other companies tomorrow and hear what they have to say.

Doug Flynn has been super helpful with the Holley system. He is very knowledgeable about EFI all together.
dougflynn@holley.com

Doug Flynn has been super helpful with the Holley system. He is very knowledgeable about EFI all together.
dougflynn@holley.com

X2,,,did an install on a 505ci pontiac last year.

Well, perfect, I'll give Doug Flynn a try and see where I come up. I always liked Holley products with their carbs. Usually takes a try or two to get them setup correct, but then they usually perform well. Again, I read the other posting about the Avenger MPFI setup and it seems to be pretty interesting.

Lead Sled,
Exactly what do you want to know, what are your expectations and uses for the car, and do you want to use a laptop or not.

Doug,

Good question. Strictly streetable and thinking about a handfull of passes at the strip just to say I did it and to see what it'll run. I don't mind using a laptop as I have to use a laptop for my tranny controller.

My expectations are to be user friendly, good tech support, good drivability, a unit that will fit under my hood, and good crisp throttle response.

Your current system is giving you fits because the injectors are so big to cover the top end with only 4 that they're not capable of metering down enough for idle. It's a dynamic range problem. pulses shorter than 1 ms are often not good with hi flow injectors. different computers and the pulsing differently too. Some are better than others at cutting the signal cleanly. Not usually an issue but with 80s it's going to be tough. Do you know if your injectors are hi or low impedance?

The Holley Dominator system will also give you transmission control.

Andrew

Lead Sled,
Let me know if want more info than I sent in my email.

WHen someone already has EFI, and has any kind of issue, like your idle issue, I always would want to understand why it is ,so that issue doesn't follow over. What Tom said is very true, but on a 496 you would usually have enough headroom.

I'd love to understand everything as well. Here's information on the 80# injectors:

http://www.siemensdeka.com/index.php?main_page=product_info&products_id=23

As far as the tranny controller, I currently have one installed already. Thanks though.

So I assume you have an EZ EFI Setup then?

No Doug, EZ EFI is not my system. To read more about the system I have is here:

http://www.professional-products.com/pp_EFI_catalog_112007_web.pdf

The Powerjection I TBI system.

When I had the 62# injectors installed, it didn't act up as bad. One thing that the information probably will not address is that the injectors are above the venturi's.

The injectors are just above the throttle plates, correct? They spray onto the plates, at least the ones I've seen.

What does the A/F ratio do at idle? Does it jump around a lot?

Yes, the injectors spray fuel onto the throttle plates. The A/F ratio definitely jumps around quite a bit. For instance, if I set the A/F ratio @ 13.3:1, it'll jump around from the mid 12's and up to the mid 14's. With the 62# injectors, with the same 13.3:1, it would stay within 13.1 - 13.5.

Do you know what the pulsewidth is showing at idle?

BPW (Base Pulsewidth) = 2.80
Injector Pulsewidth = 3.31

http://inlinethumb32.webshots.com/32479/2847317310052249461S600x600Q85.jpg (http://home-and-garden.webshots.com/photo/2847317310052249461ECxWQO)

This does not tell you *exactly* what "3.31" is, nor what the miminum increment of change is. But where you get in trouble with big injectors is where that numbers gets small (and it sounds like you are there).

It takes some time after the computer turns on the injector for the mechanical parts to actually move. This might be a count of "1" and cannot be tuned.

It also takes some time after the computer turns off the injector for fuel to be shut off. This might be equivalent to a count of "1" too and cannot be tuned.

So you have some fuel that is fixed all the time and can only tune that period in between. But when that period gets small compared to the tuning increment the tuning increment becomes a big step. Purely as an explanatory example (i.e. not real) if you add 1 to 3.31 you make a 25% change in fuel. Hard to tune with that big a jump and your system may be bouncing back and forth trying to hit the sweet spot. But every adjustment becomes a over correction.

If that 3.31 is msec... at 900 RPM you have 1333 msec at 100% duty cycle and 3.31 is a 2.5% duty cycle.

Does your setup run well enough to pull some power? What is the maximum value you see for injector pulse width? At what RPM? That can tell you what your maximum injector duty cycle is and if you injectors are just too big.

You guys keep verifying what I took a chance on before installing this system on this engine. Awhile back, I contacted the manufacturer of this same company. The guy was completely honest with me. He told me that there was a system setup with I think 92# injectors, but only after months, they discontinued making it because of the same issue that I'm fighting. The idle was poor and tuning was nearly impossible.

I'm extremely close to pulling the system off and replacing everything with a carbureted system. I've already started investigating what I'd replace it with and still researching some of the minor details for a carbureted system.

It was an outstanding little system with the 62# injectors and under 500hp. Throttle repsonse was crisp, tuning was easy and most of all, it kept the carburetor look.

If someone is interested in this setup, send me a PM. I'm still sitting on the fence, but ready to make a decision sometime soon.

Steve,
I'm out of town at the moment and will be a few days before I can check some of the information that you're asking.

My system is dated but works well for me.It was designed by Arizona Speed and Marine way back in 99.They make the intake but it is basically the same as a GM Ramjet.It is a 2 piece intake with the injectors and rails on the inside between each bank of runners.It is controlled by an Accel DFI and it is a batch fire.If I updated to sequential it would be even more tunable.Both of these controllers are fairly cheap on Ebay when they come up for auction used.It uses a 1050 CFM throttle body made by ASM.I'm running eight 36# injectors with a Vortech V1S and the motor is a ZZ502.The motor has an adjustable regulator,TPS and a GM MAP sensor.The car has a 3500 stall converter.My car idles perfect and is so responsive it took me a couple of days just to learn how to drive it properly.From a dead idle the car leaves hard with no hesitation or stumble.It kills 16.50 x 31 Quicktimes from a dead stop.I'm updating to a blower cam and stronger valvetrain right now through crazydaveyracing.com.(Very helpfull)
My setup may be too tall for a stock Chevelle hood but some guys have had the intake cut down which is no problem as it is a 2 piece.Edelbrock has some nice EFI intakes and they are under $600.They would probably clear a stock hood.EFI Connections makes everything needed to convert to a LS1 style system. Check my vid to see how the car idles.
Good luck.

1970 monte carlo ss - YouTube

.....It takes some time after the computer turns on the injector for the mechanical parts to actually move. This might be a count of "1" and cannot be tuned.

It also takes some time after the computer turns off the injector for fuel to be shut off. This might be equivalent to a count of "1" too and cannot be tuned.....


"Injector Offsets" can be tuned in any EFI system worth a darn. Tuning these variables correctly is essential to a good idle, especially in a TBI system with low impedance injectors. It is common for "too large" injectors to be blamed for a poor idle when in actuality the injector offsets are not correct. Injector open/close time varies with voltage and increases greatly as injector voltage drops which can cause starting problems as well if not correct. Typically this is tuned in an "Offset vs. Voltage" table. To set the table correctly though you should have the injectors flow tested on a bench which is not cheap. It is nearly impossible to do on the car with accuracy. In the rare severe case on a TBI system, a vacuum referenced fuel pressure regulator can be installed to bring the injector flow down at idle. There are systems out there that allow to tune for the addition of a VAFPR.

A single 4BBL TBI system can be set up to support over 700 HP with the right injectors and fuel pressure setup.

Not trying to jack the thread but the original poster did refer to idle problems and it is possible for him to use his current system though not easy.

"Injector Offsets" can be tuned in any EFI system worth a darn. Tuning these variables correctly is essential to a good idle, especially in a TBI system with low impedance injectors. It is common for "too large" injectors to be blamed for a poor idle when in actuality the injector offsets are not correct. Injector open/close time varies with voltage and increases greatly as injector voltage drops which can cause starting problems as well if not correct. Typically this is tuned in an "Offset vs. Voltage" table.

You missed my point which is that "ramp up" and "ramp down" time is not something you can change but is instead governed by the physics of the injector. You can only tune the time between ramps.

Yes there are systems that try and account for the fuel emitted during the ramps but that only goes to reduce the time between ramps by some fraction.

Yes also true that some EFI computers will monitor system voltage and adjust injector pulse to account for voltage induced change to ramp.

You missed my point which is that "ramp up" and "ramp down" time is not something you can change but is instead governed by the physics of the injector. You can only tune the time between ramps.

Yes there are systems that try and account for the fuel emitted during the ramps but that only goes to reduce the time between ramps by some fraction.

Yes also true that some EFI computers will monitor system voltage and adjust injector pulse to account for voltage induced change to ramp.

It seems my point was missed as well. What I am saying is that not only can you tune the time between ramps, lets call this the actual injector pulsewidth, but you can compensate for the ramp time as well via injector offsets. Calibrating this accurately is essential to idle quality and starting. Two examples: 1. A typical calculated idle Inj PW is in the 1.5mS range. The typical total injector offset time is around 1mS. Without injector offsets, the ECU would calculate an idle PW at 1.5mS but the actual PW would only be .5mS, only 33% of the needed fuel. With offsets, the 1mS offset would be added to the 1.5mS desired PW for a total commanded of 2.5mS but an actual PW of the desire 1.5mS so you can see where at idle, a small error in offset time can be a big deal.

2. Offset time increases dramatically as injector voltage drops and can easily double or more from 12V down to 8V. Start an engine with a weak battery where the voltage drops to 8V or less during cranking and the offsets are wrong and you're stuck. No start.

I believe this played a part in the OP's idle problem.

This is my whole problem. I don't know enough about EFI in general to know the things you guys are talking about. I see it in the program, but not knowing what kind of change I'd need to make really defeats the purpose.

I've removed the system, but still have it at home. I've started an install of just a simple carburetor, though that's not really what I wanted to do, but really had no option as I didn't understand the EFI system enough. On top of that, I didn't want to spend a ton of money on someone tuning this thing because of my ignorance.


Tom,
It seems like you know a little about EFI system, just too bad you're about 6-7 hours away from me. Otherwise, I'd check with you to see if maybe you'd want to play around with it.

I am using holley's HP MPEFI system on my 496 (about 700 hp) and am happy with it. I used the HP computer and harness along with a Vic Jr EFI intake, 55# injectors and eddy fuel rails. Using a MSD dist and computer controlled timing. Motor runs great and idles perfect; I highly recommend this setup. They also offer a Dominator system that can run your 4l80e but I don't have any experience with this. Doug F. on here helped me pick parts.

I have a separate controller for my tranny that I absolutely like. It's so simple to operate and make changes.

My issue is that I'm not ready to dump $3-4k on the newer systems. I have about $1k that I can throw at it and another 1k from the sale of my current EFI system. If I could build a system within my budget, I'd be ready for it. Seems like there are several people here using Holley systems, so I'm sure I could get some support.

Truly, I'd love and EFI system.

This is my whole problem. I don't know enough about EFI in general to know the things you guys are talking about. I see it in the program, but not knowing what kind of change I'd need to make really defeats the purpose.

I've removed the system, but still have it at home. I've started an install of just a simple carburetor, though that's not really what I wanted to do, but really had no option as I didn't understand the EFI system enough. On top of that, I didn't want to spend a ton of money on someone tuning this thing because of my ignorance.


Tom,
It seems like you know a little about EFI system, just too bad you're about 6-7 hours away from me. Otherwise, I'd check with you to see if maybe you'd want to play around with it.

Gerald, I have a brother in New Orleans which I visit often.

Seriously, I understand your plight. Unfortunately there is no "one size fits all" EFI system. There are a lot of very nice setups like the Holley and FAST EZ systems but having to fork out more money for another system after you already have one is frustrating to say the least. In retrospect, the returnless style setup you have, while convenient, makes things even more complicated. Problems arise with any EFI system when you make changes to your engine. It may be as simple as a relearn with self tuning systems or maybe new injectors or worse. Some setups are easy to make changes to or as in your case more difficult or even impossible for the EFI novice. The big companies have brought EFI a long way to make the leap simpler for the masses and their tech lines are great but the cost is not cheap. Good luck with your carb.

The system was a returnless fuel system, but I converted it to a return style. It was as easy as grounding the fuel pump, adding a regulator, and adding a hose back to the tank. This was done and I was able to keep fuel pressure and whatnot, just don't know enough about the system.

I may go back to the carb setup and who knows, maybe later I may convert back to an EFI system. If I hadn't already bought 2 carburetors, Vacuum Secondary and Double pumper and everything else to finish the conversion back to carb, I'd probably be ready to do something in the way of MPFI. My problem again comes up, I still don't know enough about them. I know I'd probably be better off with Holley or one of the other major companies as they do have tech support.

I am using holley's HP MPEFI system on my 496 (about 700 hp) and am happy with it. I used the HP computer and harness along with a Vic Jr EFI intake, 55# injectors and eddy fuel rails. Using a MSD dist and computer controlled timing. Motor runs great and idles perfect; I highly recommend this setup. They also offer a Dominator system that can run your 4l80e but I don't have any experience with this. Doug F. on here helped me pick parts.

How fast does your engine fire up? I am using a fast dual sync. distributor for sequential and it takes quite some time for everything to sync and make the initial start. I am wondering if I turned the sequential off if it would start any quicker?

It seems my point was missed as well. What I am saying is that not only can you tune the time between ramps, lets call this the actual injector pulsewidth, but you can compensate for the ramp time as well via injector offsets. Calibrating this accurately is essential to idle quality and starting. Two examples: 1. A typical calculated idle Inj PW is in the 1.5mS range. The typical total injector offset time is around 1mS. Without injector offsets, the ECU would calculate an idle PW at 1.5mS but the actual PW would only be .5mS, only 33% of the needed fuel. With offsets, the 1mS offset would be added to the 1.5mS desired PW for a total commanded of 2.5mS but an actual PW of the desire 1.5mS so you can see where at idle, a small error in offset time can be a big deal.

2. Offset time increases dramatically as injector voltage drops and can easily double or more from 12V down to 8V. Start an engine with a weak battery where the voltage drops to 8V or less during cranking and the offsets are wrong and you're stuck. No start.

I believe this played a part in the OP's idle problem.
Nope, I did not miss your point at all and I think we are talking about much the same thing. The difference is I was keeping it simplified. While you might be able to tell the computer about the ramp time and it might be able to adjust calculations to account for it, you can never reduce the time below "1" measure. And as your time count gets small, each incremental change becomes a larger chunk relatively. For example 1 out of 100 is a 1% change but 1 out of 10 is a 10% change and that larger change may well be just too much either direction.

Nope, I did not miss your point at all and I think we are talking about much the same thing. The difference is I was keeping it simplified. While you might be able to tell the computer about the ramp time and it might be able to adjust calculations to account for it, you can never reduce the time below "1" measure. And as your time count gets small, each incremental change becomes a larger chunk relatively. For example 1 out of 100 is a 1% change but 1 out of 10 is a 10% change and that larger change may well be just too much either direction.

I agree with most of this execpt where you say "you can never reduce the time below "1" measure". What you call 1 measure implies that 1 measure is a constant when in actuality it is a variable. That 1 measure can and does change with injector size, fuel pressure and injector voltage. So 1 measure for a specific setup at 12V may be 2 measures for the same setup at 8V. This must be accounted for in the calibration if fueling is to be accurate.

How fast does your engine fire up? I am using a fast dual sync. distributor for sequential and it takes quite some time for everything to sync and make the initial start. I am wondering if I turned the sequential off if it would start any quicker?
Probably cranks 2, maaaayybe 3 seconds before it cranks. I notice that it is not as fast as most late model cars, but it's not noticeably slow either.

I agree with most of this execpt where you say "you can never reduce the time below "1" measure". What you call 1 measure implies that 1 measure is a constant when in actuality it is a variable. That 1 measure can and does change with injector size, fuel pressure and injector voltage. So 1 measure for a specific setup at 12V may be 2 measures for the same setup at 8V. This must be accounted for in the calibration if fueling is to be accurate.
Argh... the inefficiency of written communications sometimes :beers:
Being a firmware engineer I approach this problem more from the computer side than the engine side. So ignore the ramp up and down time. Yes some fuel is emitted during that time but the computer cannot control or change that. Effectively what the computer *can* control is the time between ramps and this is the variable fueling possible.

The ON time will be some number of computer ticks which is the "1" or more I referred to previously. What "1" is will depend on the time resolution of the particular computer H/W and S/W and it IS fixed :yes:. The smaller the unit of time provided by the EFI computer the higher the count and finer the degree of control possible. For good tuning we want to keep counts reasonably high for the reasons I pointed out previously.

There are competing demands here though and the EFI computer may use a larger period of time as its tick period for compute efficiency (or lower H/W cost ;)).

Now to roll the ramps back into the picture... these will take some number of ticks too which can then be considered a minimum count for the injector pulse. And yes as we work in the digital world to account for analog operations in the real world we may need to bump that minimum up to deal with voltage drops. But the variable time between ramps cannot be reduced below zero and may only be varied by 0-N tick periods.

:beers::beers:

Yes EFI can be really REALLY complicated, like just about any computerized gadget these days. The real Freakin Magic is when good engineering can simplify and hide all this crap so you do not have to be a damn PhD to use the thing. The next lower level of Magic is being able to explain just enough of the FM so people can solve their problem without providing so much that they get blown into the weeds :confused: You want them to be impressed by how much you know without over achieving and giving the impression you are an egg head :p

The reason is takes time to start is the ECU needs to see both the crank and cam signals before it fires fuel and ignition (1-1.5 revs or so). Do that wrong on DIS and you have a bad deal. We may make it quicker in the future, but that is more complicated but it is being looked into.

The reason is takes time to start is the ECU needs to see both the crank and cam signals before it fires fuel and ignition (1-1.5 revs or so). Do that wrong on DIS and you have a bad deal. We may make it quicker in the future, but that is more complicated but it is being looked into.

Doug, I remember that being the one thing I disliked with my BigStuff 3. On the LS2 it only had the one synch notch on the cam gear instead of the 4 like the LS7 and others. It could take up to 3-4 seconds sometimes to synch up and fire. I even hooked up a timing light and cranked it to verify that it was actually doing that, holding the spark.

Sounds like yours is better than that, and the OEM's really have this nailed, but the technology is pretty expensive from what I've heard. I really want to try your new system in the future.

The reason is takes time to start is the ECU needs to see both the crank and cam signals before it fires fuel and ignition (1-1.5 revs or so). Do that wrong on DIS and you have a bad deal. We may make it quicker in the future, but that is more complicated but it is being looked into.

If a person was to turn off the sequential, would the start up be a lot quicker then?

If a person was to turn off the sequential, would the start up be a lot quicker then?
You have two issues here...

First is timing of fuel pulses. This one is actually not too sensitive to timing and some systems will actually start in batch fire mode until they can synch up into sequential mode.

Next is timing of ignition. This one is really the sticky wicket where you have to get it right. If you have a distributor to send the spark to the right cylinder, then you only need to synch up with a cylinder TDC event which comes relatively frequently. But if you are running multi-coil distributor-less then you need to synch up with a particular single cylinder TDC event. Those come much less frequently and are a lot harder to just turn off ;)

To answer the orignal question, you'd be hard pressed to beat the Dominator system with your current hardware and still remain within your budget. Replace both fuel and trans controls and welcome yourself to a simpler user interface in an "all in one" configuration.

Any aftermarket system that offers multi-choice input/output ignition configuration needs to have some generic control algorothms in place. The OE's have the luxury of dealing with just one engine/application so they can tighten up the sync windows because there is less chance for error. There's room for improvment on the Holley but, these take time as they're still looking to support addtional applications and enhancements which will all benefit from any global upgrades that will follow.