I am in the process of converting a 1990 IROC-Z ex-race car (rolling chassis) back into street condition. I have installed the engine, and even had it running briefly. I thought that I had everything all worked out, that is until I attempted to install the factory '91-'92 oil cooler (RPO KC4). The oil cooler tubes have a support bracket that attaches to the block at one of the mechanical fuel pump plate bolts, and the cooler tubes occupy the same space that the pump does. Since I have a mechanical fuel pump this is a problem. I figure that the mechanical pump will have to go.

I am posting this on the TPI board because I want to know if I can use the stock in-tank pump to supply the fuel, and some sort of bypass fuel pressure regulator to reduce the pressure to the 5 psi required for the carb? There is no fuel tank in the car now, so any changes can be done fairly easy. Or mount a new electric pump near the tank? I would like to leave the original type pump/pickup in the tank if at all possible. Are these approaches feasable?

Thanks, ANDYZ28

 

Yes. You'll have to bypass the extra fuel that the efi pump supplies. Otherwise it works. - I've done it(not on a hi-po set-up) simply running a "t" with a valve on the return line to regulate presure at the carb. If you're running any type of preformance motor, I would recommend running some type of bypass regulator to properly meter the fuel.

 

I am sunning the 406 SBC very similar to the one built by Chevy High Performance Magazine http://chevyhiperformance.com/techa...s/148_0306_406/

I guess the ideal situation would be to use an in-tank pump that only produces carb friendly pressure, but I don,t know of anyone who makes one. Otherwise I am going to use a bypass type regulator as you have suggested.

Thans, ANDYZ28

 

I have decided to run a TBI in-tank pump due to it's much lower pressure, along with a return type regulator. But can this pump deliver enough fual at WOT on the street? I only see aftermarket pumps available for TPI. I am sure someone on this board knows the answer.

Another small problem has surfaced; It seems that I must run the 7730 ECM for my speedo and cruise to work properly. Will I need to run "a" prom for this to work. Sorry, but I gotta have my cruise!

I have an ECM and the two black plugs that connect to the ECM, but where does the yellow plug come from?