[DQ81]

I have an engine out of a 90 G20, it's a 350 TBI that I've got in my 81 Blazer now.

I kept the vans wiring harness.

I have the ECM and the two small black plastic boxes that are on that end (what are they?)

I also have a ECM sized black box that was/is plugged in on the Fusebox side and I'm wondering what it is and if I need it. I'm trying to elimnate everything I don't need to run the engien and feed the gauges info.

Anyone know what this black box on the right is for? To the left of it is the bulkhead side of the G20 fusebox:






After looking at wiring diagrams for both I'm at a bit of a loss at how to integrate the TBI harnass into my 81's

I can figure out the ignition to starter but am at a bit of a loss as how to power the ECM. If the ECM gets 12v at start/run does that feed all the sensors too?

[DQ81]

BUMP:

Anyone?

Or a good site where they might now or be able to help me out?

thanks

[jerryvarnell]

whats a g20?

and youd have to look up the wiring diagrams of both the g20 and 350 tbi, see which wires match to be able to power it correctly, and splice the wires. because it obviously isnt the same. you SHOULD just be able to plug everything in, but it doesnt seem compatible.

if it was me, id just rip the intake off and throw a good high rise intake on with a carb. you said you didnt want it to be very electrical just mechanical and thats the only way to get rid of the wiring.

[DQ81]

Originally Posted by jerryvarnell

whats a g20?

and youd have to look up the wiring diagrams of both the g20 and 350 tbi, see which wires match to be able to power it correctly, and splice the wires. because it obviously isnt the same. you SHOULD just be able to plug everything in, but it doesnt seem compatible.

if it was me, id just rip the intake off and throw a good high rise intake on with a carb. you said you didnt want it to be very electrical just mechanical and thats the only way to get rid of the wiring.

A high rise is wrong for this application on this motor without other mods. It's in a truck, bone stock. It needs to keep it's low end torque and I'll never get it over 5k rpm.

A G20 is the standard designation for a 3/4 ton Chevy Van from about '73 to 96

Like K5 for a Blazer or C10 for a half ton pickup....

Never said didn't want it to be too electrical, just nothing I don't need. I want the TBI for a reason. WHEN it works, it's more economical and powerful. In addition, it's there AND LPG like it better.

Anyone else have any idea what that box is?

It's not in the Haynes Engine and Chassis wiring diagrams or online. The TBI harness, engine and trans were all pulled form the same vehicle: The 1990 G20 Chevrolet van

[DQ81]

I just had a thought. It looks very much like this ABS module and so does the wiring:

ABS Module pic

agreed?