Fuel-Injection on a '75?

[Thore826]

I've found these forums to be very helpful. I had a question regarding fuel injection conversion on a C3, in my case the '75. On another form someone mentioned getting a TPI manifold from a 85-91, wiring harness, and chip to pretty much have it running like a C4. The only modification I have to the engine right now is headers with sidepipes, and my carburetor is on its way out. Anyone who'se done this; could you tell me if it'll affect the sound? Do carburetors have any distinct sound that fuel injection doesnt have? I know it sounds vain, but I get compliments all the time on the exhaust, and if it comes down to that muscle-car sound or better fuel economy and running, I'll take the sound.

 

[Thore826]

I've been reading more on this in other threads, and did some outside research and found this:
A TBI fuel injection system requires the following components: A TBI throttle body and intake manifold, a computer (a.k.a. ECM; electronic control module), a GM electronically controlled distributor, an electric fuel pump, a fuel filter, one pressure-safe post-pump filter, and a fuel return line to tank. Also required is a MAP (manifold absolute pressure) sensor, an electric spark control module, fuel pump relay coolant, a temperature sensor, a knock sensor, one oxygen sensor, an oil pressure switch, a vehicle speed sensor, and wiring harness
How to install GM TBI on any Chevy V8
Does that sound about right? I heard on some of the threads that I need an electric fuel pump in/on the tank; if I have one on the engine, will that do just as well, so I don't have to modify/change my existing tank? And I'd still like to know if anyone has done this before, and whether they think it's worth it performance-wise
Thanks

 

[Art Jett]

I have TPI on my 383 stroker and love it! It is an aftermarket system howevwer and more expensive than using a stock GM system. Along with the extra expense, you also get much better performance than you would with a stock system. If that is not a problem, you might check out Affordable Fuel Injection on the internet. My system with powdercoating was about $2300.00 with all sensors, wiring and computer. It comes with complete installation instructions and troubleshooting guide. They ask you for all your engine specs, and drive train specs and burn a chip for YOUR car instead of hoping a stock chip will do the job. Real nice people to deal with also. Good luck with your choice. PM me with your E-mail address and I can send you some pics of my engine. Art

 

[minifridge1138]

I've been reading more on this in other threads, and did some outside research and found this:
A TBI fuel injection system requires the following components: A TBI throttle body and intake manifold, a computer (a.k.a. ECM; electronic control module), a GM electronically controlled distributor, an electric fuel pump, a fuel filter, one pressure-safe post-pump filter, and a fuel return line to tank. Also required is a MAP (manifold absolute pressure) sensor, an electric spark control module, fuel pump relay coolant, a temperature sensor, a knock sensor, one oxygen sensor, an oil pressure switch, a vehicle speed sensor, and wiring harness
How to install GM TBI on any Chevy V8
Does that sound about right? I heard on some of the threads that I need an electric fuel pump in/on the tank; if I have one on the engine, will that do just as well, so I don't have to modify/change my existing tank? And I'd still like to know if anyone has done this before, and whether they think it's worth it performance-wise
Thanks

That list sounds about right.
As for the fuel pump, you do need an electric one. I've always heard that it is easier for the pump to push fuel to the engine than it is to suck it out of the tank, therefore you want it as close as possible.
Also, the in-tank pumps are submerged in gasoline and use that as a coolant to keep the pump from over-heating.