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I'm doing a rather unconventional swap. Putting my SBC 400 and a 93 4l80e into a 96 k2500 rolling chassis. The chassis originally had a 6.5 diesel. The guy that pulled the engine chopped the wiring harness to pieces. 

    OK here it is, the truck had an electronic throttle nine wires. I need to wire in my three wire TPS to the PCM,   IF POSSIBLE! My fear is that I'm screwed and that there is no way to accomplish this without spending seven or eight hundred dollars,  That I don't have!

   I'm also still struggling with some of the wiring from the transmission. I finally found decent understandable wiring diagrams at Mitchell manuals. Even they do not show the second Transmission Speed Sensor, nothing and nobody, that I've found does! At this point I'm five wires short of getting this beast on the road. I've been driving myself crazy on this for nearly five months now, and I want my truck back (for the first time, sort of)

                                  Any help would be much appreciated,  Thank You!

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92-93 they changed the 4l80E connector, do you have the newer or older style connection?

Have you opted to pull a wiring harness from a 93-95 Chevy 1500 at a junk yard?

94-95 has a good ECM for 350 that will run a 400 fairly well. Plus you can get a 4l80E EPROM that will run it. 

You will need the VSSB to run the transmission and speed signal.

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The tranny is a 93, But I'm pretty sure it has the newer style connecter.  I have the ECM from that truck and wiring harness.  I was initially hesitant to use that ECM because the 96 has ABS brakes and I was worried it might not function properly. However I have learned that the brakes have their own computer.

   I'm not sure if the one I have will work as it was for a 6.5 diesel, with manual throttle. All is not lost I know where I can find a variety or computers, if need be.

Edited by Wildone59
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On 2/14/2019 at 4:26 AM, Mikebtte said:

92-93 they changed the 4l80E connector, do you have the newer or older style connection?

Have you opted to pull a wiring harness from a 93-95 Chevy 1500 at a junk yard?

94-95 has a good ECM for 350 that will run a 400 fairly well. Plus you can get a 4l80E EPROM that will run it. 

You will need the VSSB to run the transmission and speed signal.

Thanks for the kick-start. I had to think about this for a while to get my brain to wake up and come out of the fog.   The ECM that I already have for the 93 diesel should do just what I need. It is the same one that WAS paired with this transmission.  Because my 400 is a gas engine with an HEI the TPS that I got from Holley should provide all that the ECM needs to make the 4l80e work.

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