anyone have experience with a Holley Fuel Injection system?

NJ2000R · #1 (**permalink**) 05-01-2003, 09:50 PM

I've got the Holley Pro-Jection-4 system on my 427 SO (it came with the system on it) and I find it difficult to maintain adjustment....does anyone have any advice on how best to tune the damn thing? or should I pitch it and get something else?

Tom Wells · #2 (**permalink**) 05-02-2003, 05:46 AM

Hi NJ2000R

Which Pro-Jection do you have? What are the symptoms? What do you have to keep adjusting?

Tom

mrmustang · #3 (**permalink**) 05-02-2003, 10:45 PM

Have you spoken to Bruce K. at the speed shop in Rockaway??

Bill S.

NJ2000R · #4 (**permalink**) 05-03-2003, 04:18 AM

Tom - Its just Pro-Jection 4 as far as I can tell....

Bill - no, not yet....

I'm going to wait til after my electrical system is gone over....The original owner of the car left alot of things unconnected, not grounded properly, or just plain done the wrong way....I did screw around with it last night, and got it somewhat adjusted....seems like heat is a big factor....once the engine got hot, I adjusted the knobs as instructed, until it idled correctly and didnt sputter at acceleration....also found out the car got real hot - because the guy who built the car has the fan blowing the wrong way! oh well, after a few days with my electrics guy, we should be fine....I just wish I had more free time to spend going over the car....working 7am - 6pm is good for putting money in your pocket, but you cant do much of anything else....hopefully we slow down a bit....

petek · #5 (**permalink**) 05-03-2003, 08:38 AM

I've got a Holley ProJection 4Di on my 351W. Works like a champ. I'm still playing around with the fuel map a little bit (runs too rich during warm up). Started with 10mpg and now have it at 15mpg.

One BIG difference between the setup you have and the one that I have is that the one you've got does not have an O2 sensor. Without the O2 sensor the FI never goes into closed loop. Closed loop mode means that the FI computer measures the O2 in the exhaust and makes adjustments to the fuel map to keep the mixture perfect. The only time the 4Di is not in closed loop is during warm up or in WOT. I'm pretty sure Holley sells the parts to add the O2 to the older ProJection units.

Loosing power to the FI computer should not be a problem, I know it's not a problem on mine (the computer holds the map in a EEPROM).

NJ2000R · #6 (**permalink**) 05-03-2003, 10:54 AM

this one does have the 02 sensor, so we probably have the same systems....I'll keep playing with it til I get it to work, what I need to do is just run the car once I get the electrical stuff sorted out, and eventually I'll figure it out....while driving it over to the shop today, I must have had everyone around looking at the car....gotta love open pipes!

jhaynie · #7 (**permalink**) 05-05-2003, 06:06 AM

I have a Holley Commander 950 FI system on my 351W. I've had the car for about 9 months and until recently, like you, haven't been able to spend much time on it (built a house). I recently discovered that letting the car warm up well before getting on the road makes a huge difference in the performance. If I don't let it warm up, the system has a stumble from 3000-3500 rpm all day long. If I let it warm up, the stumble isn't noticable. Doesn't make much sense, but this is an extremely complicated system (in my eyes anyway). I'm going to keep trying, hate to throw away a $1500 + system this early in the game.

petek · #8 (**permalink**) 05-05-2003, 08:14 AM

If you have the 4Di system you should be able to connect a laptop computer to the FI computer and watch the various sensor values and injector settings. Watch the O2 compensation value to learn how close to optimal your fuel map settings are.

jhaynie, at what engine temperature does your system go closed loop? I've got my 4Di set fairly low (160 degrees). The engine warms up pretty quick to 160, but the engine also acts a bit "cold" before it warms up. Still, it's *much* better than carbs!

jhaynie · #9 (**permalink**) 05-05-2003, 08:29 AM

Don't know the temperature Pete. I plan to spend some time on that in the next couple of weeks. I need to find a person I trust to drive the car while I work the computer, or at least someone computer wise.

NJ2000R · #10 (**permalink**) 05-05-2003, 08:32 AM

is there a special program needed ? where do you connect the laptop ? mine may be pre-computer accessible (guessing its around 1992 vintage, when the previous owner built the car)

petek · #11 (**permalink**) 05-05-2003, 11:03 AM

There should be two connectors coming from the FI computer. One connector is a DIN-5 (or something close), barrel shaped, plugs into the box with the knobs. The other connector is a DB-9 and plugs into the serial port of a laptop computer. The laptop computer then runs some software that Holley provides (give Holley a call, I'm sure they could send you the software).