Who is running Holley HP efi ? What do you think of it pro's or con's. I am ready to set up my 509 and have a manifold, fuel rails and 48 lb injectors.

I just installed the Holley Dominator EFI on my Vette with a solid roller 555". It's essentially the same thing as the HP but with added features. Replaced a 1050 Dominator that I've used for years and had very well dialed in for street use. The EFI started out very close and within just a little time was doing as well as or better than my carb dreamed of. Cold starts are instant...driveabilty is really sweet. We just did a 2500 mile road trip with it and had no hiccups.

We had just barely got it off the dyno and in the car before we left...so it had no street driving time at all.

Recently I started playing with it and it's really sweet stuff. You can tune it by target A/F ratios, or pounds per hour and just let it do its thing. I have the DIS ignition too...so I have a lot more flexibility there than I had before. In fact I just went out tonight and put about 70 miles on it with my wife driving while I was playing with the laptop. I was able to pick out targeted areas and lean them and bump timing for nice lean part throttle cruising and verify that as I mashed into it, it would add fuel, pull timing or combo of each to make it dead smooth...and it did!

So far, I'm nothinbg but very pleased. It started out right where I had spent years tweeking my carb to get to...and just keeps getting better.

I don't think you will be unhappy at all.

Check with Doug Flynn here...he will clue you in on all you need to know!

JIM

Jim, how far were you able to lean out cruise? Also, what are you using to drive the oil pump?

Thank's for your input Jim. Sound's like it's just what i want. Where did you purchase your system. I have looked on line and not found much for part# and price's.

Check this place out. Will give you a great price, but more importantly this person can offer you any technical help and knows what parts you need. Something the "big places" can't do.

http://www.mooreracecraft.com/

The system(s) are very new so there aren't a ton of people out there driving them yet. I can answer any questions you have about it, but will leave "comments" to those that have it.

Jim's Dominator system uses the software as the HP and other than drive by wire, trans control, and extra inputs and outputs is the "same" as the HP.

Right now I have it at 15.5 A/F ratio and 46* timing under cruise conditions. Not a hiccup once. I'm going to run it in that area for now and see what fuel mileage acts like. We had it locked in the 13.2 range on the road trip..so it definitely can be leaned a good bit.

My oil pump is driven by one of those *distributors* that provide a cam sync signal.They used them in some 90's pickups. It's called a GM sync pulse distributor with an AC Delco PN 213-350. They are being reproduced..but you *can* modify a regular MSD to run the DIS...or you can use regular ignition systems.

And again, to give you an idea of driveability, my wife jumped behind the wheel last night and drove it just fine....G-Force crash box and all. And I still haven't swapped out the throttle body with the 1 to 1 throttle linkage. Man..that thing is touchy...talk about response! In fact....I'm starting to like it...a LOT!

JIM

Thanks Jim, but your killing me (in a good way)!

So you use the sync pulse "distrib" to trigger the DIS coils? So you dont have the crank trigger kit that mounts to the damper?

I know my motor will cruise at 15:1, its just that when I lean a carb out that far, it creates too many "holes" in the fuel curve, and the motor runs rough here and there.

Sorry to Wanye70 for the highjack, but hope you find this info applicable!

Right now I'm using the crank trigger only. I'm not using the cam sync signal yet to control individual coil groups timing. Sneaking up on everything I can do with this thing...and it's a LOT.

I know what you're talking about...getting a carb to transition from 15.0 to just a little bit less....or a lot less takes some work. I spent a long time getting mine to work the best for my setup. Little bit of Voodoo in there to get what you want when you want it.

When the engine is running, it indicates on the screen/table exactly where it's at based on all parameters. There's a *dot* that moves around as you accelerate. Of course it moves to different parts of the table based on vacuum and RPM. So for example, there is an area for WOT at say 3000 rpm and an area for light throttle cruising at 3000 rpm (or whatever RPM you want to look at). You can assign what A/F ratio you want at any particular point and it will do it by adding or subtracting fuel from your base tune. You can have it go from 15.0 to 11.0 with a slight throttle movement if you wanted it to. Of course you likely wouldn't...but you could. You can monitor how much fuel it is adding/subtracting at any point. Once you work out general fuel points you're playing with, you can also go to a 3D map table where it graphically shows your fuel (or timing curves) and lets you see those *holes* you described. You can either go back to the tables and make changes, or do a *click and drag* on the 3D table to smooth them out. Once you tell it what you want....it just does it.

You can also do the same with timing. You can pick any RPM/Vacuum point and set timing to what you want. Think of it as an infinitely adjustable timing curve. You can add timing just like vacuum advance would under light load..or at idle...and then take it to whatever you want as load increases. You can also program in a *timing retard* so to speak so that it pulls it out at high RPM if you want to. This can be done manually or by setting up logic that tells it to retard/advance based on your inputs.

All of this sounds pretty involved...but it's really not. The Holley System comes with a series of base tunes that are based on your cubes and cam. I started with one of those and it fired up and ran fine as it *learned* on the dyno. It just took the base tune and added/subtracted fuel to achieve the same A/F ratios on MY motor combo. The trick is in the base tune. That's where tons of time has been devoted...to get you that close. You could just put it on and go drive around and let it learn and it would do it. I've done that...now I'm just playing with the fine tuning stuff to see what I can get away with.

I'm a die hard carb guy.....but I have to say I'm getting spoiled quickly. I haven't had one drop of gas on me since I started playing with this thing and I've got boxes of jets, PV's, gaskets, air bleeds etc that are getting lonely!


JIM

I actually downloaded the Holley EFI software from the Holley site, and been messing with it. The software is designed in a very user-friendly way...very methodical and intuitive. It's actually fun!

Thanks Jim.

No problem Vince. More discussion is more that i can learn from.
Is the DIS worth the extra cost for a street car? My hope is to try and get 18 -20 mpg on the highway in a 70 chevelle with 3.70 gear and Gear Vendor behind a th400.

questions.

what does the back of this unit look like. I cannot find a single pic. what i/o connectors does it use?

2. dual fuel implementation - is it possible to switch off on set of injectors and switch on the other set at a predetermined MAP or rpm?
im thinking I could use 42lb injectors for idle and just above, and switch to the big injectors or use both after like 3000 rpms or so. is this possible?

3. are there analog style gauges in the software?

questions.

what does the back of this unit look like. I cannot find a single pic. what i/o connectors does it use?

2. dual fuel implementation - is it possible to switch off on set of injectors and switch on the other set at a predetermined MAP or rpm?
im thinking I could use 42lb injectors for idle and just above, and switch to the big injectors or use both after like 3000 rpms or so. is this possible?

3. are there analog style gauges in the software?

there is no need to turn on and off injectors like that. I have friends running 2100CC injectors on their hondas that start and idle perfect and make 600WHP and do it with 4 injectors.

there is no need to turn on and off injectors like that. I have friends running 2100CC injectors on their hondas that start and idle perfect and make 600WHP and do it with 4 injectors.

thanks, I appreciate the reply. im more curious if its possible though. there are some situations where it may be helpful, for example if wanting to set an extra set of injectors spraying race gas from a different fuel tank, or meth, etc. Im just curious if the holley software has the capability

The secondary injectors are blended in gradually based on duty cycle. Most systems use a "hard cut" which can cause a shift in the fuel curve. Unless they are paired together on the same outputs due to driver availability, then they all fire at the same time which would be the case on a HP with an 8 cylinder with 16 injectors. A Dominator has 12 drivers so the second set is ramped in.

thanks doug.
now, why did holley not program the software to show me a gauge page? thats the only thing Im missing while playing with the softare.

oh, that and I dont see where to change dwell settings for the ignition coils.

edit: I found the dwell time under custom ignition. thanks

Be nice if Holley releases an app for something like an Iphone so a laptop doesnt have to be lugged around - that would be real neat!!!!