Al Jackson

Has anyone installed a Holley Fuel Injection system ( such as the Commander 950, either the Throttle Body or Multi Port type ) on a C3 ??

djgrelli

I haven't installed one on my vette, but I put one on my son's 87 Jeep Wrangler. We put a small block chevy in it. It wouldn't pass emissions with the holley on it so I installed a Holley Pro-Jection system on it with an O2 sensor. Runs pretty good and passes Maryland's sniff test. You're going to need a return line for the fuel tank if you go with any kind of fuel injection.

Cookwithvette

I have installed the commander 950 kit on a zz4 in my vette. Another member around here, Zwede, has installed it on a 454 in his vette.

joe78

I have installed the edlebrock pro flow system it is a lot of work but is awesome had the motor on the dyno with it on 430hp have it tuned perfect now.

Fast81

I've got the Pro-Jection 2Brl TBI unit feeding Fast81 since 1998.
Haven't added the closed-loop add-on (O2 sensor feedback).
Don't beleive the BS about needing the 4brl unit for more than 300hp, I haven't maxed the settings or the fuel pressure on my unit to feed the mods described below

zwede

There's info on the Holley 950 install on my webpage (in sig). If you have questions after reading it, ask away.

Al Jackson

What's your web page ???

zwede

I guess you have your profile set not to display signatures?

Here's the link:

http://www.corvetteforum.net/c3/zwede

Al Jackson

Thanks for the info. Great pictures. Does the stock air cleaner assembly fit under the L88 hood with the MPI system ?? I really wanted to keep our 72 as stock looking as possible. The price for a Holley MPI system is now $2800.00. When you put the ECU under the dash pad on the passenger side did you have a GM stereo adapter for the FM radio in the way ?? Did you use an external fuel pump ??

zwede

Never tried the stock aircleaner, but I did run an aftermarket open element aircleaner for a while. It was one of those $30 chrome drop-base aircleaners. I did have to cut 1/2" off the manifold to make it fit (detailed on the webpage). If you have a smallblock it should fit fine without cutting.

I have a modern stereo so I removed the old stereo amp a long time ago. You could probably fit it if you really wanted to. There's quite a bit of room.

Yes, I'm using an external pump. The one I show in the pictures on the webpage is the old Holley EFI pump. Holley now supplies a newer (better) pump made by Wal-Bro. My old pump started making noises about a year after install. Holley sent me a wal-bro pump at no cost. The wal-bro works great and is very quiet.

Al Jackson

I noticed you ran a new 3/8" aluminum fuel return line. I have three more questions.
1). Did you have to lift the body off the frame to get the fuel line between the body and frame ( god it's tight ).
2). I believe my stock 72 Big Block has a total of 3 fuel lines. One on the drivers side ( 1/4" ) for the fuel evap system from the canister back to the tank. Two on the passenger side of which one is the 3/8" fuel supply line and the other is a 5/16" fuel pump return line back to the tank.
I believe the 71 was quite similar to this. If so, why didn't you use the 5/16" fuel pump return line instead of running a new line ? Thats my plan if it will work.
3). Are you using the fuel evap canister any longer ?

PS Thanks for ALL the info. This is a huge help as you have already been through this.

Al Jackson

zwede

Nope, didn't lift the body. The 3/8" line follows the brake line most of the way. If you take your time it's not bad. Just be careful not to kink the al line.

I heard conflicting advise on the 5/16 line. Some said it was too small, other said it was fine. I decided on a 3/8" return to be safe. If the return is too small, pressure will build up in the rail especially at idle and it will run rich.

I'm not, but I could hook it up if I wanted to.