Do yourself a favor and switch the harness. It will save you a lot of trouble.

 

boy you guys are all across the board in what needs to be done and what doesnt.

anyone who has specific questions and wants the correct answers straight up, pm me.

radiators are different. k frame not only lets the v8 sit lower but diff mounts, fuel pumps are different, same pressure, diff volume, steering rack is diff on z28. transmission crossmembers do vary. a/c lines are not the same. underhood harness is diff and has things like leads for both fans and low coolant level sensor.

 

Well that's indeed the case as everybody who says they have done it comes up with a different approach and many questions are left unanswered.
I recall asking about the 2 extra injectors (fuse + wiring) months ago, nobody replied .......

I said it before and i'll say it again, NOBODY to this day performed a 3.4 to LT1 and actually documented (photographed, trouble shooting, etc.) properly, the thread which is pages long in the V6 Tech section says enough.

I WILL do all that as i don't believe in reinventing the wheel so i'll make sure it's documented step by step.

 

Well, i did some research and spend about 8 hours into studying schematics and the good ol' shoebox.
My research is based on a 1995 3.4 Fbody swap to a 95 Lt1 engine.

This is what it comes down to:

The ONLY reason for a complete forward wiring harness would be for the dual fan setup (wiring, relays, connectors), however this can be solved with 2 additional relays and some extra wiring that can be tucked into the existing wire loom, nothing major there.
The rest is IDENTICAL !

The injector Mythe is BS, the only purpose as far as the forward harness is concerned is feeding the injectors (through engine harness) with 12V coming from the underhood electrical center (driverside under the hood).
The V6 harness has ALL the wiring needed, in fact it features the 12V wiring in the correct location for both the V8 application AND the v6 application so it has in fact more injector feeds then needed , luxury problem ... When connected to the V8 engne harness through connector C100 and 105 these extra feeds for the V6 application will be redundant.

As for the indash connectors from the engine harness (C210,C220,C230) they are simply plug 'n play and need NO modification either.


So summing it all up, the ONLY reason for swapping the forward harness is a plug 'n play dual fan radiator setup, otherwise you would have to add 2 relays and do some soldering and adding some extra wires in the wire loom which isn't too much work.

Oh, in case you are using a T56 in the swap and you want the Low coolant warning to work you need to run a single wire from the sensor to (other wire is put to ground) the gauge cluster, it's a very simple setup.

I agree that a forward harness would make it all plug and play but don't underestimate the removal and reinstallation of that harness which isn't done in half an hour.

 

Hello okay I just can't really find the exact answer i wanted so i hope you will know. I have a 1994 v6 camaro and I just bought a wrecked 1996 z-28. the thing I was really wondering about is what wiring will i all have to replace i know the PCM, but what about the engine compartment fuse box on the driver side will i have to use the 1996 compartment box? Also will i have to replace the fuse box inside the car with the windshield motor fuse lights ect.. with the 1996 fuse box or can i still use my 1994 one but some how replace the compartment box you said you found out the hard way and I've tried to fallow what you were explaining so did you have to replace all the inside wiring too? if you could reply me back it would help me out alot thanks...Keith

 

When I did mine I went 93 - 93 and still changed everything. I would strongly advise you to change over both the engine harness and dash harness. This will lessen the chance for trouble when its time for you to enjoy the car. A few extra days now is much better than a teardown once the engine is in.

 

So the dash hardness is that all the wiring for the switchs and everything inside? or just to the fuse box on the drivers side? because that looks like that would be a really hard process b/c won't i have to tear the dash all apart and rewire everything or is it all plug and play? thanks

 

The switch harness should be fine, but you will need to change out the under steering wheel wires that go through the fiirewall into the engine harness - SO everything works with the PCM.