1988 5.7 tbi

[stevensonmotors]

Hello
Looking for tips and info for installing a 1988 chevy 5.7 TBI motor and 700r4into a 1959 Apache. I have a new original gauge cluster and a new original wire harness that I would like to keep do I have to keep the computer ugh

Thanks
Bob

[octanejunkie]

Originally Posted by stevensonmotors

Hello
Looking for tips and info for installing a 1988 chevy 5.7 TBI motor and 700r4into a 1959 Apache. I have a new original gauge cluster and a new original wire harness that I would like to keep do I have to keep the computer ugh

Thanks
Bob

Hi Bob, contracts on your '59 Apache, it's a popular model around here

To run TBI you need a computer, also called an ECU, but it doesn't need to be the GM original. Look at the aftermarket, like Holley or FAST, you can buy their ECU and adapt it to factory fuel injection. I have the Holley Avenger 550-400 kit in my truck but there are plenty of guys on the Holley EFI forum running factory TBI and MPFI applications with the Holley ECU. If you are a "roll your own" electronics DIYer you can also look at MegaSquirt.

I would recommend a new wire harness overall. Modern accessories need larger gauge wires than the stock trucks had, and you will (should) use relays for things like the horn, lights, electric fans, fuel pump, etc. and you'll probably end up cutting into that new harness. EZwire and Painless make great aftermarket harnesses and have plenty of circuits for extra goodies the stock harness didn't, plus adds a modern fusebox and uses the correct gauge wire. You will also want to upgrade your ignition system to computer controlled ignition, but you can stick HEI or similar if you prefer. I went small cap HEI and let the ECU control timing.

Just know that you will have a at least two different harnesses, one for the truck (lights, dash, gauges) one for EFI (ECU, sensors, TBI) and possibly one for the transmission depending on which model 700R4 you have.

Having done all this myself, I know it seems daunting from the outset but it's all pretty straight forward and there is plenty of info out there and in here.

Good luck and start a build thread!

[stevensonmotors]

Thank you sir!

[Bad Apache]

A couple other ideas. If you can get the factory harness and ecm from an '88 truck, with a good diagram it would be very easy to swap into your truck. The 88 700R4 trans has a lockup torque converter, so it would be nice to have it functioning. GM electronics of this era are very easy to work with. Don't let them scare you. They operate on 9-13 lbs of fuel pressure, so you won't need an expensive fuel pump. You will need to run a return line from the throttle body to the fuel tank. The other option is just buy an intake, carb, distributor and torque converter controller.