'90 T-IV to '91 R/T wiring conversion

[Directconnection]

Who has done a '90 P-body (or any SBEC for that matter) conversion to '91 R/T electronics conversion before?

Contemplating on thinning my herd, and just going with a T-III transplant into my '90 T-IV Shadow next year.

I have NEVER done a conversion before, and figure an SBEC to SBEC should be the easier of the bunch to do. But, using an existing R/T harness in plkace of the original T-IV, what about fitment as the Spirit one may be wider/longer?

How much hair pulling will I be looking into... relocating things, etc...

I know this is easy for some of you guys, but this will be my 1st time around.

[turbovanman²]

Jackson and iTurbo should know,

[jonnyb]

Steve - you still have your TIV harness?

That would probably be the easiest to use - you only have to lengthen/move a couple wires in the engine compartment and everything else is pretty much plug and play (seem to recall throttle body sensor wires needing to be lengthened, and needing to pull temp sensor wire out of bundle so that it can reach over to temp sensor on side of head - maybe one or two other wires).

If you go with the R/T harness, you'll have A TON of work to do under the dash. The R/T uses a single bulkhead plug under the dash, where the p body has the multiplug bulkhead. So if you went that route, you'd have to splice and solder all 50 wires in the bulkhead, and there's some tricky loops that you'd have to make sure you don't miss (the p body has wires under the dash that loop from one mini bulkhead connector to the other, so it's not a 1 for 1 splice from the rt harness to the p body harness).

And yes, Jackson definitely knows about the ease of converting the TIV harness - he posted up the details about a year ago either on this site or on td.com - that's what made me change gears from using an R/T harness in my 91 vert, and going with the 91 T1 harness instead. Hmmm...wait, now that I think about what I said above - mine was a 91 so I already had the correct coil pack wires in the harness - since yours is a 90, you'll have to change and re-route those wires too (I think you'll have to actually add a wire as the 90's had a single coil driver wire and the 91+ had two driver wires). Still, making a half a dozen changes under the hood is a heck of a lot easier than the 50+ under the dash.

Jon