got a 90 awd shell, going to put in a 91 engine

[jay-red]

Just like the title says, i just picked up a 90 talon awd shell, and going to take the engine out of my fwd laser rs to put in it. I have read that there are some differences between the 90's and the others. I was wondering what i need to keep off of the donor car? Both cars are complete but the 90 has a blown engine.

I assume i need to take the engine, wiring harness and ecu out of the laser, but is there anything that i might run into that im not aware of?

 

[Rex2342]

Just swap the block and head from the 91 and use everything else from the 90. Since both cars are complete this would be the easiest method and the 90 car could retain all its "unique" components.

 

[Redwidow]

"unique" = Harder to find

 

[rlacasse1]

Easiest way would be to do as rex2342 said to do.

 

[Rex2342]

"unique" = Harder to find

exactly! With that said you could still swap everything over from the 91 to make it easier for future repairs. You would need portions of the 91 wiring harness and several other parts. Off the top of my head you would need:

91 Throttle body and wiring for all the sensors
91 CAS and wiring
91 coil, power transistor, and wiring
91 AWD ecu and modified harness
91 Gauge cluster


I think that's about it for the wiring. There are other parts that are different from 90-91 such as the oil filter housings and some of the transmissions from later 91s but yours is a FWD so it wouldn't matter. I would keep the 90 oil filter housing though.

 

[jay-red]

I read something about swapping the awd flywheel onto the donor engine, is this needed since its a fwd car? So the "easiest" way is just to use the head and block, but the "best" way is to use everything from the 91? besides having some hard to find parts, is there any real benefit? I thought i heard the throttle body is better on the later ones?

Also, is the ecu different between fwd and awd? I know they are different between 90 and 91, but i didnt think that awd or fwd would make a difference?

 

[Rex2342]

I read something about swapping the awd flywheel onto the donor engine, is this needed since its a fwd car? So the "easiest" way is just to use the head and block, but the "best" way is to use everything from the 91? besides having some hard to find parts, is there any real benefit? I thought i heard the throttle body is better on the later ones?

Also, is the ecu different between fwd and awd? I know they are different between 90 and 91, but i didnt think that awd or fwd would make a difference?

I'm not 100% certain here but I believe the ECUs have different tuning parameters from AWD to FWD. Maybe someone who knows more about this could chime in. You will need the AWD flywheel too. I don't know about any benefits using the later parts other than them being more common. I've never really had an issue with finding stuff for my 90 but the 91-94 stuff is usually cheaper. I'm going to eventually swap my throttle body and CAS over when I get time but it's mostly so I can eliminate the FAIV easier. If you need the car running just do like I said and use the 90 parts since the car is complete and it would be faster. Save the harness and the parts from the 91 so you can swap them out if needed.

 

[808DSM]

Well if the flywheel off the 90 AWD and is in ok condition just use that. But, since your taking everthing from the 91 and pulling the engine anyways just get a new flywheel. Yes, the FWD and AWD Flywheel are different size.

 

[jay-red]

So i got the engine out of the talon today, the passenger side axle was seized into the hub, first we used a 2lb hammer, then heated it for a couple minutes, then hit it with a 5lb hammer and still wouldnt budge. So he kept heating it and pounding the hell out of it and it finally started to move. Then it was too far in to hit but still wasnt loose so he got out the roto hammer (i believe thats what my grandpa called it) to move it out the rest of the way. It finally came out but we destroyed the threads doing so. It was so flared out we had to get out the grinder so we could make it fit out of the hub.

Everything else went as planned, and i have decided to use everyone's advice and just swap over the block and head and keep the 90 components. One weird thing happened earlier though, before we took out the engine i wanted to do a compression check and see if the "blown" motor was really bad. As soon as there was power the started kicked on by its self and ran for like 5 seconds and stopped. So i said screw it and just did the check any way with it doing this (got 160,0,160,165 btw) Any idea what caused this? I dont want this to happen when i put in the new engine.

 

[jay-red]

so i have the engine in and mostly wired up. I have to put out there that there is way more differences between the years than just the parts listed here. (these at least were different from my 2 engines) The egr is different, the vacuum solenoids are different, a sensor on the water neck is different, the vacuum rack thing under the intake manifold is non existent on the 91 engine. Im sure there were a few other things, but thats all i can think of right now.

I should be finishing it up in the next day or so after i make sure i have the wiring correct, i found out that there were a few plugs that all fit into each other so i had to look up where they went.

 

[jay-red]

Just wanted to update this for anyone searching in the future on what i had to do to make it work.

First i did what i had planned and just used the block and head while swapping over all parts from the 90 car. Couldnt get spark and there was some weird problem with the starter. So i decided to swap everything from the 91 car, essentially "converting" my car to a 91.

So i put all the 91 stuff back on (throttle body, cas, coils, fuel rail etc..) had to take out the dash on both cars to get the wiring harness out. Once i had the harness in i went to plug it in where there are the bunch in the passenger side foot well. Found out that one large white plug doesnt work between the harnesses, but the wires all match up so i just swapped the pins over to the plug that worked.

Kept on putting it together and found another white plug near the yellow ecu ones that didnt match up, swapped the pins again and ended up with 3 wires that didnt plug into it, not sure what they did, will look it up later. I also swapped the gauge cluster for good measure.

The car runs and idles perfectly right now, the only issue i ran into is that the temp gauge doesnt work, i swapped sensors to see if that helped but no dice. Will look into it tomorrow, but as of now its up and running.