im swapping my motor from one camaro to the other.

when i pull the motor out, i plan on putting TPI on it while its OUT of the car.

my question is should i attach the harness and all the sensors and stuff BEFORE i put it into the other camaro? or should i put it in THEN attach the harness.... seems like more of a pain to do it that way though?

anything else i need to know along these lines?

 

I would put the harness on the engine and then install it... that's what I did with my L98, and all I had to do from there was run the bulkhead back into the car. Made everything a whole lot easier.

Just my opinion.

 

I second that. Wire up everything you can while the motor is on the stand. Drop in the motor and plug in the bulkhead connectors. Make sure you put in the screw that holds the connectors in or else you'll be chasing electrical gremlins for weeks . It's also a good time to route the harness in a more aesthetically pleasing way. Like for instance, instead of running the wires over TOP of the brake booster, run them underneath of it. It makes everything look better.

 

<b> Drop in the motor and plug in the bulkhead connectors.</b>

what are those?

<b>Make sure you put in the screw that holds the connectors </b>

and what are those / where are they?

i have never installed a harness before, are you saying wire the sensors to the motor and wire the harness in the car THEN put the motor in and plug it all together? and would those screws be in my TBI harness or my TPI harness or both?

 

If you plug the harness in to the engine, and then install it, It will be SO much easier. Read on for more info.....

The bulkhead is where the entire engine harness comes to an end at the "trunk" of the harness (found on TPI and TBI setups)... this will feed in to the car via the psgr side fender (all the connectors and such, pretty easy to spot). The DASH part of the harness however, connects on the driver side of the engine compartment at the firewall (underneath where the relays are mounted). There should be a "box" looking connector on the harness that will plug in there, along with a 6 or 6.5 mm bolt that holds it in place. Be sure to tighten it down after you plug the dash harness section in, otherwise you might not have a good connection. If I'm not too clear on this, sorry. If you have any questions I'll be happy to answer them as detailed as I can be.

 

I would like to clarify some things. The bulkhead connector is the big black box, it's really just a big plug, on the driver's side firewall next to the brake booster and below all of the relays. The 'trunk' of the harness that feeds through the passenger side fender goes to the ECM. It will all make alot more sense when you take the original harness out of the car.

What motor is in the car now? There are quite a few things about the swap that most people don't mention that I came acros when I did mine. First off, I had an L03. I swapped an L98 to it.

#1) the injector wiring was different b/c I had a '90 car with an '86 harness/ecm that I was putting into it. Somewhere between those years GM decided to change the under-dash plug. The main problem was that the injector power feed wires on the car's harness didn't match up with the wires for the injectors on the '86 harness, so I had to wire them up to a circuit that was controlled by the ignition.

#2) Different years use different plugs on many of the sensors. I had to cut and splice quite a few of my plugs from the L03 harness. Don't use connectors when doing this.....always solder them!

#3) The vehicle speed sensor buffer on the '90 car didnt match the plug on the '86 harness, so I had to make an adapter for this. Don't skip this part. If the VSS buffer isn't hooked up , it will messup your timing, your convertor lockup and will make tuning the car a pain in the butt.

 

well i have a harness from an 89 TPI 305 car, the harness in my car is an 89 L03 TBI harness, i dont plan on using the TBI harness, i plan on removing it and installing my TPI harness, or is that what you thought i was doing?

The VSS of both should match up right? how does the VSS get its reading? directly off the tranny?

ANd what do you mean about the injector power feed? where is that and what does it do? since im replacing the harness, does any of this apply to me?

WIll i still need to use pieces from my TBI harness, even though i have a complete TPI harness? sorry for all the questions i have never done this!

 

you are keeping it the same year, that's a good thing. Using the complete TPI harness, you probably won't have to do the above mentioned items. The VSS is located at the rear of the transmission. Are you using the same tranny? There should be a VSS harness already plumbed into it, and if you're using the same trans, you should be good to go (they are both automatics, right?)
You need the 305 ECM and PROM... do you have them? The L03 is different. If you have the TPI ECM, you shouldn't have problems.

You are going to have to change your fuel pump too, don't forget. TPI and TBI flow very different fuel pressures. The fuel pump harness will fit a TPI fuel pump, so you shouldn't have any problems there.

 

first off im sorry to mislead you but im not putting TPI on my 305. im pulling the 305 out and doing... not sure what yet with it...

im putting in a carbed 355, but putting TPI on it first. i still need the ECM and a 350 chip to get started.

<b>The VSS is located at the rear of the transmission. Are you using the same tranny?</b> i thought the VSS was in the actual speedo unit until 1990...

Im aware i need a fuel pump, i ordered a high pressure in tank walbro unit from autotronix already.
i also just picked up a maf sensor. i want to start with maf because i have no chip burning skillz and maf is more forgiving i have heard. its already got the maf relays on the harness too..

the TPI harness is from an 89 automatic im pretty sure. even if it isnt shouldnt be a big deal since i gota get the ecm and chip separate anyways. im trying to get everything i will need before the 305 comes out though, its my daily driver right now the carbed 355 coming out tommarow, so both cars will be down for a bit. i want it to go quickly.