Holley Projection

[PlasticBoob]

Carb

It's a really tough choice. I would say carb for sure, but the only thing is that I don't trust any carb to give reliable operation when it's sitting most of the time. That's where the Pro-Jection shines.

In my experience, carbs like to fail. No, they LOVE to fail. They revel in it like a pig in mud, even squealing like one as the engine struggles to start. Every carb'd vehicle I know regularly has fits at the worst possible time, and especially after they sit. I gave my shiny new Truck Avenger to a friend to use on his Blazer. It worked flawlessly on my Jeep (aside from hard starts on hot days due to fuel evaporation due to annular boosters), but then I gave it to him and it started having all kinds of issues because he only started it once a week and drove it once a month. Constant sticking choke and fast-idle issues, and then it finally ended up flooding out over the vent tubes after idling for a few minutes. It must have only had less than 10,000 miles total on it. I know because I bought it new. He doesn't know carbs and I'm busy, so he ended up having to go take it in for a "rebuild". $$$

You might want to see if you can get the Pro-Jection working, but I wouldn't waste too much money or time on it because when that wild analog box starts to fail (if it hasn't already), it's going to throw even the most tech-savvy for a loop.

[DarkMonohue]

First thing to note, he inherited the system from the original owner, so it [Holley Projection] was what was on the truck...the source of the problem is the Fuel Delivery system. I feel as if a good quality carb will give him the reliability he needs.

There's no doubt that the fuel delivery system is involved. However, my concerns are these:

1) That the problem may originate within the fuel system in general, including tank, lines, filters, and all, and may not be limited to something that would be removed if you replaced the Projection unit with a carburetor.

2) That the problem is likely to be caused by dirt, moisture, or corrosion due to years of disuse, rather than by a faulty component or design flaw of the Projection system.

Either of those situations could mean that, even after replacing the Projection with any other fuel delivery device, you'd still have an unreliable vehicle.

But if someone has clear suggestion to make this system reliable, that would be ideal. I am not sure that answer exists.

That's pretty much why I am harping on the idea of a really thorough cleaning and inspection. That way you can be sure that any fuel delivery device is able to do what it is designed to do.

[PlasticBoob]

That's pretty much why I am harping on the idea of a really thorough cleaning and inspection. That way you can be sure that any fuel delivery device is able to do what it is designed to do.

True. My friend with a J-10 had some issues with stalling out and choking randomly after we went offroading one day. Turns out there was a hole in the gas tank that was patched with JB Weld. It had broken off and fallen into the tank while offroading, and would randomly get sucked up against the pickup (that didn't have a sock on it, btw).

[EasTXJEEPER]

I have read all the replies pro and con and think all I need to do is have a co-pilot with the ECU in his lap and a small screwdriver in hand to see if tuning in actual driving situations helps with making things right. It is definitly tuned only by feel and seat of your pants performance.
Taking a nosedive in traffic like it did is a white knuckle experience I don't want to experience again especially with the wife on board.
I had 2 Chevy Astrovans with TBI and NEVER had any fuel issues with either one in hundreds of thousand miles. Changed a fuel filter in 1 once when it wouldn't go faster than 40 wide open. But that was not the TBIs or electrics problem.

[ProTouring442]

Has anyone thought to check the ignition system? How does the saying go, 90% of all carburetor problems are electrical.

The OP's description sounds just like a failing coil.

[DarkMonohue]

Has anyone thought to check the ignition system? How does the saying go, 90% of all carburetor problems are electrical.

The OP's description sounds just like a failing coil.

Holy crap, you're right. Very right.

But shame on you for interrupting a witch hunt in progress!

[jslabotsky]

Has anyone thought to check the ignition system? How does the saying go, 90% of all carburetor problems are electrical.

The OP's description sounds just like a failing coil.

^^^ What he said. Plus a coil is cheap and takes 5 minutes (or less) to swap out.

What kind of shape is the fuel pump in? IIRC these units were designed to run on low pressure from stock, mechanical pumps. But if the pump is getting a bit tired, I don't think these units have something analogous to a float bowl to act as a buffer when there's a sudden increase in demand. So if the pump is too weak to keep up with demand in real time, I could see that making it fall flat on its face.

I'd look at the basic tune up items. If you've done all of that and are frustrated, and want the path of least resistance, swap it out for a carburetor. There's no shame in going with what you know. Not really any large gains is driveability or performance to be had here without spending more than you wanted to.

If you decide to get rid of the Pro-Jection unit, I'd take it off your hands. PM me.

[jdaniel83]

The pump on my Pro-Jection unit was an electric pump that came with the Pro-Jection kit and I believe it was rated at somewhere around 20-25 PSI. There's a built in pressure regulator on top of the throttle body that uses an allen wrench to increase or decrease the pressure. I can't remember the size but for some reason 5/32" rings a bell.

[jslabotsky]

The early ones only required 15 PSI but it seems reasonable they would have come with an electric pump. Anyway, fuel pressure is something to check. They sell a fuel pressure regulator service kit.

[Tinkerjeep]

I agree with what many others have said here the fuel SYSTEM may be more of an issue.

Though my opinion re carbs...I do remove and clean out my Edelbrock 1405s after every 12-24 months of use.

Here is my fuel system on my 4-door J20:
32 gallon steel fabbed fuel tank behind the rear axle. A 5-micron can filter just ahead of the tank. then a mix of stock hard/softlines to the electric fuel pump mounted to the inner frame rail. then that feeds forward through more hard/soft line to the area near the brake booster where both my feed and return line run. the feed line goes to a stock-type "bypass" filter, then around to the feed side of the edelbrock to a glass, inline filter then to the carb. the bypass line returns to the tank.

Even running 3 filters I still get very fine black particles and rust particles in my carb bowls. The black particles are likely rubber from the inside of my soft-lines. which are Fuel rated. And I have had this problem since LONG before the gasoline refineries were forced to put Ethanaol into their fuel. So its really an issue with the crap rubber made these days for fuel lines.

What is my point?

Even the best, finest filters will allow contaminants to reach the carb or TBI.

Having said that, and given my DD's fuel system, I would rather clean an Edelbrock carb out every year or 2 than clean a Holley...and that goes double for any FI system.

As far as the carb's going bad...loaning your stuff to dubious "friends" to wreck is asking for trouble. You have NO control over what fuel went into that carb and if it had massive contaminants in it. I've never experienced any of my Edelbrock carbs "going bad" after a decade of using them exclusively...Holleys though - that's another story. Routine cleaning is a matter of importance for anything that gets used though...how often do you shower? Same deal.

[AM Woody]

Sure it could be other things, but this sounds more or less consistent with my experience with analog Projection. My 89 had it installed when I bought it. It ran smooth and strong. When it ran. I added a closed loop kit and got a fast pass on the IM240 emissions test. It never left me stranded anywhere but my garage, but I had a few no-start situations that were a pain to diagnose. It ended up sitting a lot.

There is nothing to "plug in" to. The only thing you could do with a laptop is if it was connected to an external exhaust gas analyzer for tuning. The closed loop unit can be used as a tuning aid. As far as the Holley Projection "manual", the troubleshooting section is a joke. The best info I got was from people here that were running them.

So, I gave up on it and put a stock carb on. The truck has been starting and running for about three years now, which is much longer than it would stay operable in the six or so years I had it with the Projection.

[dan01ster]

I installed a Pro-jection system on my 360 J20 back in 1995. Within the 1st yr it had one of the two injectors go bad...acted somewhat like the issue here. The next year it had the fuel pump (electric came with the kit) fail. The last failure for anything was in 1997. It has run flawlessly ever since...nearly 20 yrs now and it sits in winter storage for 6 months of the year and never has gas additive put in the tank...fires up and with 6 month old gas goes to the nearest gas station and gets a tank of premium to start the season off.
Call me lucky from the sounds of it. It is an open loop system...no O2 sensor and is analog with the rheostat knobs on the ECM. Initial tuning does need to be done per the manual and that takes a copilot and a tach. with some nice open non busy road.
If you do need to replace the injectors, don't buy a holley unit,, it's the same part/performance as an injector for a Dodge Dakota 5.2L from around 1995-6 or so and much cheaper if you get one from a jobber ie NAPA/UAP under the Eclid name.

[EasTXJEEPER]

Holly Projection goes away

Well Guys. Here it is mid October of 2015 and as I type this post my tempermental Holly Projection is being replaced by a 4 bbl carb.
To be sure everything was in perfect working order from the filler neck to the fuel pump we dropped the tank first. What a mess, If was rubber it was brittle and cracked. Suspected problems when I let the electric inline fuel pump empty the tank of 10 gals of gas. Fuel Pump was pumping half gas and half air. Took over an hour and half to empty the tank of 10 Gallons . I Suspect blaming the projection for dependability problems was more the fuel delivery system than anything else. Got on the pipe with BJ and ordered all new rubber fuel delivery parts from the filler neck forward.. If they got the order out today, Friday, I should have them by Tuesday.
I'm not even going to look back on trying to salvage the old Holly analog system even with the fuel delivery fixed.
I spent most of today in town running errands and getting the results from a recent CAT scan. Doc is not sure of what he sees is cancer spreading or not. Ordered a PET scan for next week . Here's praying that test is negative.
In the mean time my talented kid was under the hood working at what he does best. He was off to town when I got in and the shop was locked. I will check again after supper and give you all a progress report.
It has been a long time coming getting this tired old 83 Cherokee Laredo East Texas Barn Find dependable. Even with all its problems it always got me home.
If anyone is interested in a used complete Holly Projection drop me a PM.
When it did work it was great and fun to drive.
Kenny

[EasTXJEEPER]

Son Chad of Chad's Classic Cars got the swap done by 3;00 PM and got the 360 running fine on a nurse tank.
He went to town to get ignition tune up parts and a inline fuel filter with return line.
As soon as the Fuel tank parts from BJs get here Monday the tank can go back in and we should be good to go. Kenny

[CutterN55]

I'm workin on my Holley Projection 1D on my CJ7's 258 right now. I had it tuned well and was pulling around 17mpg fill up to fill up by calculating the pump numbers. I then jacked up the tune when I went up into the mountains on a wheeling trip. I had trailored it up and when I unloaded and wheeled around in crawling gears it was fine but when going between trail heads my acceleration sucked... fell on its face and bogged down. I was an idiot and started fiddling with the tune thinking it was an altitude issue. On the way home I was thinking about it and realize that I had probably sucked up a bad tank of Marine gas from the gas station I used on the way up.

That accounts for my fuel pressure on the supply line at 6.5psi and crappy spray pattern when I give it gas. Clogged filters, injector, and I went and screwed with the tune and boogered it all up.

For anybody still messing with these things... they are much easier to tune with an Air Fuel Ratio or Lean/Rich Indicator and O2 sensor so you can continuously monitor AFR throughout the RPM ranges while you are driving. All adjustments should be made Open loop with the O2 disconnected if equipped. Once you are close, the closed loop system will take care of the rest on the fly and I think it has around 20% authority to auto adjust.

The 29 page manual from the holley website is way better than the pamphlet that comes with the system. Off the top of my head...
-Set all the knobs on the ECU to Neutral all flat in a line left to right in respect to the mounting plate.
-Set the mechanical idle on the Throttle Body with the fast idle solenoid wire disconnected.
-Meter out the TPS with the throttle plate fully closed, look for .63-.65 volts and screw it down. Should increase smoothly to 4.5 or 5 volts at wide open throttle.
- Adjust the Main knob on the ECU for fastest pass on road test 1000-3000 RPMs in 2nd gear at Wide open throttle.
-Next is Idle on ECU. If the idle is still off, you might have to go back and redo the mechanical idle then the TPS and Main again.
-Once that's good, move onto Accel. Do a rolling takeoff from about 20mph. Mash it note the response. If it puffs black smoke and bogs its rich, bogs and no smoke its lean.
-Then do High RPM (3000+) just like the Accel shot. Smash it from a constant 3000 RPMs speed in probably 2nd or 3rd gear.
-Choke is last and will take a few tweaks over a couple days of cold starts.

Plug everything in and run it and see how it does. When these things work, they work awesome. Hope this helps somebody in the future.