Holley Pro Injection

[pyro fighter]

I just picked up a holley pro injection kit from one of my buddies. Does anyone know anything about these? Its looks like a TBI, comes with everything. He said that it kept burnin up electric fuel pumps, i think 4, He got pissed off with his bronco being down all the time and put a 2 bbl back on. He said if i could figure it out I could have it.

Well now I have it, and I know nothing about it, or anyone who runs one. Anybody used these before? Why the fuel pumps keep going out? Is it even worth my time?

Thanks for the help.

 

[Broncobowsher]

OK, there are a half dozen different versions of the projection. Many are garbage, a few OK, and fewer are actually nice.

If the box has screws on it for adjusting the engine, I think 5 of them, keep passing it along to another "friend". It is either on old analog system or maybe an early digital system.

If you have a computer interface, it is looking promising. O2 sensor, then it has potential.

Look at the computer.
4D = junk. Digital system that is not that programable
4Di = might work. Digital interface. There are actually 2 versions of this. You need to open the computer and look at the ROM and see if it is a 2 or 3 series. I have 2 and have issues. I hear that the 3 is much better but have yet to try.

Now if the box says "comander 950" then you have a workable system. That is a good computer.

but beware that unlike the EEC Ford based EFI that is plug and drive, you will need to do serious tuning to make the Holley stuff work.


Now you will get advise on this baord regarding Projection. Unless they actually state which version of projection they are refering to (analog, 4D, 4Di, Comander 950) then they are blowing smoke out there...
The early ones left a bad taste in many mouths and many are blind to the other versions that actually exist.

 

[Rockin69er]

I rescued a 4DI system from my friends garbage can a few years ago. No one could make it work. To many problems to list. Since the price was right I gave it a whirl. After replacing the computer, TBI unit, wiring harness and fuel pump I got it to work. Only problem I had left was 1 out of 10 times pulling out from a dead stop it would accelerate like it had nitrous. I live in a valley at 3500 ft and to go anywhere is up to 6-7000 ft and it had to be reajusted when I got there and again when I returned. More trouble than a carb. I know 4 people with Pro jections and the vote is .....1 for and 3 against.

Update; I just talked to the guy who likes his Pro Jection, He said if it was running OK but burning up fuel pumps it is 1 of 2 things. 1-return line to small (this usually makes it run rich) or 2- fuel pump mounted to far from tank ( electric pumps are "pushers" not pullers) and they are overheating. Any other ? I will ask him for you.

 

[pyro fighter]

Hey Thanks for all the info. I'll have to check up on all this. I'll let you know what I find, but it sounds like I should give it to my buddy down the line. But what the He!!, what can I lose if it doesn't work then I will slap my 2bbl back on there.

 

[bludorbronc]

I have the one with the adjusting screws on front, it works good for me.I run 3/8 fuel line to and from the unit,Holly wants zero lbs return pressure. check you have good ground. There is an optional wiring loom so you can run a O2 sensor for somewhat auto control.