Thread: Hilborn 8 Stack Electronic Fuel Injection

Tweet

Had this installed on my 496", full roller, BBC and the tuner is having difficulty getting it dialed in. It's getting closer but still spits through the stacks during in-town driving. Runs good on the highway but is still pretty glitchey in-town. It also doesn't want to idle (wants to die) when the engine gets a little hotter than highway temps. It idles great until full operating temp. I'm running a Holley ECU. I researched 8 stack electronic fuel injection units before buying this one and it's my understanding that these are supposed to run really well both on the street and strip. I think an experienced tuner could have this thing humming in short order.
I've had it back to the tuner numerous times but we don't seem to be making any more head way and I think he's getting tired of looking at it. Add to that, it's his first experience with a Hilborn electronic unit. It's close, but no cigar.

Are there any tuners experienced with this type of electronic fuel injection within 300 miles or so from southeast Iowa that could get this thing really well dialed in...once and for all? I'd be willing to drive there and stay over night if necessary. Thank you.


Tom

Tom,
I'm no "tuner", but I've messed with my Edelbrock unit a bunch and I can tell you what worked for me. From your comments I'm assuming that your Holley ECU is NOT self learning, and that it is programmed via 3D maps and correction curves. I can tell you I was lost until I bought a wide band O2 sensor that I could mount in the exhaust with no leaks, feeding a digital fuel/air ratio indicator I could watch for tuning. Mine was more difficult because of the short lakes style headers and no tail pipes. With a passenger watching the numbers and taking notes, you drive around in your "problem areas" of the map. A data logger would make it quicker, more accurate, and much easier, but an indicator works. Now this assumes that you have your Spark Map nailed down, and that you're not making changes on two fronts at one time - that'll get you mired in the mud quicker than anything if you're chasing a problem.
The key to getting mine "happy" was the built in correction curves that modify the map based on coolant temperature, and it sounds like that may be your problem, too. I got my Fuel Map where it was working right for WOT, then cruise, then worked the transitions. The F/A vs coolant correction is basically the "choke", but the curve goes all the way out to extreme hot temps, too. This is your cold idle, transition through mid-range as it warms toward normal, and then compensates above normal just in case. The one that really kicked my tail was crank fuel vs coolant temp, which is the amount of fuel injected to get responsive starting in all temperatures - mine was veeeeery sensitive in the transition area where the curve is near vertical.
It sounds to me like your guy has the spark and injection maps pretty well set, but that he may not be spending enough time on the correction curves, assuming the Holley uses a similar interface to that of the Edelbrock unit.

Sorry Tom, but I'm 319 miles!!!!!!!!!!!!!!!

Does it pop on any specific cylinder???????????and at what water temps/inlet air temps??????Did you install any type of idle air control?????????????

Is it a unit like the one on the 32 ford on pages 4/5 of my gallery????????????

Um, what? LOL!!! Hey Roger, sounds like a completely foreign language to me. I'm just a driver and not much of a do-er, if you know what I mean. I have some very basic mechanical skills but I just need to take the car and turn it over to someone with enough experience to super tune the EFI and be done with it.

BTW, the Holley ECU is self learning. But my unit must be mentally challenged as it hasn't learned much so far, ha, ha. I was just wondering if there was an experienced EFI tuner around Des Moines, Kansas City, Omaha, Chicago, the Quad Cities, Minneapolis, or somewhere in between with the necessary familiarity and experience to get the job done first time. I've been taking the car back to my tuner and he and his main engine tuner have tweaked the unit 6-7 times now and it doesn't seem to have gotten any better. I'm really getting frustrated.

I probably don't have to tell you this is a fairly high dollar unit and I'm expecting it to run like one. Fortunately, my engine tuner hasn't charged me much beyond the initial installation fee for any follow up tuning (which was considerable since there was a LOT of plumbing involved). But, so far, I don't have much in the way of results either. IMHO, part of the problem is the tuner probably hasn't driven the car enough after tweaking it. Not only do I think driving the car after tuning is critical but it needs driven for a good 1-2 hrs and allowed to get COMPLETELY to operating temp. Right now, the engine will idle OK up to about 200 degrees. But if it gets much hotter than that it will start a cyclic surging, kind of like a car with a supercharger. The RPMs get lower and lower and the engine dies and doesn't want to idle until it gets a little cooler. It still starts OK but doesn't want to idle.

Anyway, it still needs a good bit of sorting out. My tuner lives an hour and forty minutes from me and I'm really tiring of the drive to have it tweaked. I'm just not sure where to turn at this point? Andy Starr at Hilborn has been really cool but he can only do so much and the tuner has to be able to take it from there.

Anyway, I'd appreciate any recommendations for experienced EFI tuners. I know I'm really going to like this unit once it's dialed in. I just need to find someone who can get the job done. Thanks again.


Tom

If I were going to a shop in the KC Metro it would be MC Racing - http://go-mcracing.com/ . They have built a good reputation of solid work, and they have a tuner who knows how things work. I'm sure you can find a good shop in the Des Moines area with a few phone calls. It'll become apparent pretty quickly who everyone in the region uses for their heavy tuning work in programmable ECU's, but you're looking for a guy who can work with the aftermarket stuff as well as tweaking OEM computers. That can be a different world, and the guy who may be aces on factory stuff may stumble with a Holley, FAST, or Edelbrock. You want the guy who knows both worlds.

While I have been waiting on answers to my questions, I went thru the threads you have posted and found some pics of the car and one that I was able to enlarge enough to see some details-----------Amoung possible other factors, the water flow back to the radiator from the front of the intake manifold (looks like 2 -8 lines?)--
as a comparison, stock oem engines have an inch and half or larger upper radiator hose----------

You have entirely too high of under hood temps which cause many factors to change at a rate that a self learning system can't keep up-------------

Now--how about answering my questions----do you have any type of idle air control or are you just using the throttle blades???do you have an inlet air temp sensor???????????Is it any specific cylinder/s that pop?????????????/

Jerry,

Thanks for your response. I wish I could answer your technical questions but I simply can't. I'm very ignorant on this subject. I can tell you the engine runs pretty cool (195-200) until you turn the a/c on when it's hot and humid outside. The temp then starts to creep up to the 220-230 range.

Yesterday we had to use the street rod ('40 Chevy Sedan) to chauffeur a bride and groom in a wedding party. We had the a/c on and the car spit through the stacks 30-40 times during the 2 mile trip and then I had trouble with the car idling after the engine started to heat up. It was actually running very good before yesterday. But I think you're right, the water hoses need to be bigger. I had no heating problems at all before installing the Hilborn injection. And the tuner warned me that we might have to go to bigger bungs and hoses. I can see how this might confuse the ECU. I just know so little about this. I really need an expert to take the ball and run with it.

Tom

Tom,
Try Karl Performance in Des Moines - Karl Performance Parts They seem to be a full line shop, serving the whole gambit from OEM to Street Rod to Racing. You might call them and chat before investing in driving over there, but it looks like a good place to start that's not too far from home.

I have a Enderly and Fast electronics on a 502 bbc. Believe me its not really made to run at near idle speeds. These are racing manifolds made to run at full throttle. I have similar problems. Your surging is cause by a lean condition. Some of these units like the Fast have a base program that you cant change, may not work for your application too many variables. Wont go into learning until it hits a certain engine temp. Manifolds don't have a plenum, so no idle air control. I have a small aluminum block with air brake hoses to each runner under the butterfly, doesn't really do a good job though. Lots of things to check to try to make it run better. Fuel pressure and a proper regulator is another. Do you have a return line to fuel tank? You have to sync all cylinders with a synchronizer and tweek each butterfly to get them flowing all the same, very time consuming. These are just some of the thing to do to try to get it running better.

KC

Tom,

First off, are you running a Cam Synch or DIS (what do you have in the distributor hole, and how is it setup in the Computer)? If not, you are not running the Injector in sequential mode, which has a history of doing exactly what you are suggesting-popping through the stacks. This means you are running it in batch fire, which will fire the Injector when it is not needed-sequential can help with that-

#2, are you running one EGT sensor or two? (the Holley can run two, which can give the Computer more resolution).

Have you adjusted the manifold and done the arc adjustment/synch?

Jerry, I know that Hilborn generally does not run a IAC (mine doesn't have one), and in discussions with Andy Starr, on a Hilborn C396 anyway, he says they do not use or need one for EFI.

Tom, If I were you I would call Andy Starr at Hilborn (he was in the California location last week, try there)-I believe next to Doug at Holley he is your best resource to fix this-

As for the idle after it warms up, obviously this is a seperate issue, as the Computer changes it's parameters when the coolant temp goes above a preset value (say, 180 degrees), so that can be adjusted, and you should be able to get it to idle correctly-

I found an outdated list of tuners in a Car Craft (?) Article (not many Holley tuners as it is the newest system out there), but again, either I would call Andy or the Tech line at Holley-they will help!

Originally Posted by KC33

I have a Enderly and Fast electronics on a 502 bbc. Believe me its not really made to run at near idle speeds. These are racing manifolds made to run at full throttle. I have similar problems. Your surging is cause by a lean condition. Some of these units like the Fast have a base program that you cant change, may not work for your application too many variables. Wont go into learning until it hits a certain engine temp. Manifolds don't have a plenum, so no idle air control. I have a small aluminum block with air brake hoses to each runner under the butterfly, doesn't really do a good job though. Lots of things to check to try to make it run better. Fuel pressure and a proper regulator is another. Do you have a return line to fuel tank? You have to sync all cylinders with a synchronizer and tweek each butterfly to get them flowing all the same, very time consuming. These are just some of the thing to do to try to get it running better.

KC

KC, thanks for posting about your system. I learned a couple of things - made me go look at the IAC loop to sort out details on them. I'm interested in your aluminum block with air brake hoses plumbed to each runner below the butterfly. Can you maybe post a picture or two, and an explanation of what you've done? Just curious, but it might also give Tom another nugget to share with whoever he gets to sort out his system.

Thanks so very much for all the info guys. Keep it coming. I'll turn it all over to whoever ends up tuning my EFI. And I will try Karl Performance. Thanks again.


Tom

Roger,

mine has it too, (it's for vacuum operated accessories)-

Originally Posted by 35WINDOW

Roger,
mine has it too, (it's for vacuum operated accessories)-

OK, that makes sense. I was under the impression from KC's post that it had something to do with simulating Idle Air Control, which as KC pointed out is for a single throttle body/plenum approach. Lots of good info in your post!! Thanks.

There are many things that go into an intake system that has individual runners-----cam timing and overlap, header design(runner length), any exhaust leak?, getting all the throttle blades at the exact same setting(this can then vary side to side on the engine as the engine heats up, especially with alum heads)

The Hilborn on the 32 in my gallery(if you haven't looked, please do-there are also more pics of it in some posts) was built by me a few years ago---It has a Fast sequental system on it--

The length of the injector stacks as well as header length were some of the prime factors we dealt with---

I also fabricated an idle air control system that uses filtered air source and tubes going to each injector base--

I located an IAT(inlet air temp ) sensor in the cowl at the rear top of the engine bay

I incresesd the size of the h2o lines from the front of the manifold to a thermostat housing for coolant return to the radiator----

I used an MSD dist with a second trigger in the base for phasing the injector timing

Used a filter,pump,regular,return line fuel system for control of the fuel and everything is isolated from any exhaust heat----


There are dozens of basic mechanics involved in this plus dozens of tuning issues----I don't believe that a learning system will ever work satisfactorly because the system will never be in a correct mode for it to adjust from---

These systems need considerable chassis dyno time to get base lines for different cruise conditions with over lapping areas of acceleration, coast, idle, etc

In looking at the pics of this car-----------heat build up is going to have to be dealt with and corrected along with doing more to adapt what is basicly a very good system for wide open racing to the real world of put in the key , turn on the sterio, set the a/c, and hit the cruise scene-------------