Fox T-Bird/Cougar Forums  

I swapped a 2.3T/T5 into my 86 Cougar 5.0.  The swap is very straightforward.  I didn't do much research and there wasn't information to be found as most people swap a 302 into a 2.3T car instead of the other way around.  I just figured that both cars were 86 Cougars (my donor was a $200 wrecked XR7) so if I move everything from one car to the other it should work.  The XR7 donated it's engine, transmission (C3), wiring, exhaust, instrument cluster, interior, wheels, and other odds and ends.  I later got an 87 TC that donated it's T5, brakes, rear end, steering rack, sway bars, intercooler (and hood), big VAM, LA2, and some other stuff.  Everything with a few minor exceptions went together without much trouble.

I have a build thread, although it doesn't go into too much detail on the engine swap itself.  http://www.foxtbirdcougarforums.com/showthread.php?27461-My-86-Cougar-%282-3T-swapped%29-thread-%28long-and-lots-of-pics%29

Feel free to ask any questions.

Welcome...

I'll start by asking how good of a wrench twister/sparktrician are you??

Reason being about the only thing that a '87 or '88 Turbo Coupe shares with the std Birds is the body, most of the mechanics and electrics are on a different level... Think 5.0 AOD Stang for a V8 Bird(with 4 cyl brakes) as far as basic mechanics... The Turbo coupes have the larger 5.0 Stang brakes with rear disc, plus there is the now troublesome electric ABS & ride control system that it's unique struts & shocks are unobtanium(many TC owners have deleted these systems)... Also are the electric fans that are controlled by ECM 

Sooo the correct way to make the conversion is swap all the mechanicals and electrics which includes all the under hood, dash other harness... Nothing for either car's electrics is directly compatible with the other, if you don't swap it all you'll be splicing and adapting(swapping to 5.0 in a '87-'88 TC is far easier than the opposite)... The 2.3 ECM test port is in the ABS/ride control harness, so if you delete it(or at least don't strip out the connections), you won't be able to scan ECM... This has happened on some hack conversions to std brakes... Fuel lines are different in engine bay(connect on opposite sides), if your TC is severely rusty you'll want to run new lines...

This just touches on the high spots, rarely does a swap such as this actually happen... Member Chuck Warren has done so but his is a far less complicated 1983(?) and I'm not familiar with what changes he's actually made...

My 85 turbo ran perfectly but had a miss at high RPMs. It turned out to be a burned plug wire shorting against the engine. Easy-peasy.