I have an 88 N/a and it smokes white. I'm thinkng I need to replace the motor. I found an n/a FS but it's from a 90. Does anyone know if ll have any problems with this swap and if so, what?

 

well for one s5 engines are Different... You can use an S5 block but i think you need to change the whole front cover.. S5 engine have electric OMP and s4 has a mechanical

You need to use the same ECU but OMP on the s5 will put the car into Limp mode if you dont have the omp pluged in..

Cant use any of the Upper intake... Im sure there is more.. But people do it all the time.. If you take the cover off and put the s4 cover on and use all s4 parts on the engine you should be fine

 

You didn't post a lot of info, so I'll assume you meant that you have the whole long block, not just a bare engine keg. If so, be sure you have the corresponding ECU and you'll be fine.

 

Yeah I've got the whole long block.. S5 Harness and ECU.. Will Everything just plug in to the original S4 stuff??

 

of course not. search around some, this question is asked every week.

 

Unfortunately, no, an S5 engine won't plug in to the s4 stuff. You have to rewire everything. An s4 engine is typically strongly recommended or else paying a shop a bundle to do the complicated wiring work or having a great deal of know-how yourself. I hear an s4 engine into an s4 car is just plug and play though; wouldn't know first hand.

 

It shouldnt be that hard. I once put an s4 engine on an s5 body. As long as you have the full harness you can figure out things.

 

It's actually quite a task. You did the opposite s5 engine into s4 car is a whole different job altogether.

 

yeah it is a pain in the ***, I figured just use the manifold with the rats nest and all to make it as plug and play as possible.

I am using an s4 harness, ecu, full intake manifold, leaving the s5 front cover and running premix.

 

im sure there is way more to it than just plug and play.

 

Use your S4 ECU, harness, injectors, sensors, etc on the S5 block. Keep the S5 intake manifold and search for ways to activate the 6pi and VDI. You may need to adapt a few S5 connectors to the S4 harness. The BAC wires may need to be extended a little bit as well.

You'll have to use your S4 throttle body on the S5 manifold to retain the S4 TPS (actually, I think you can wire up the narrow range part of the S5 TPS to an S4 TPS plug, but it's probably easier to just switch TBs). If you're using an S4 OMP, you absolutely need to use the S4 TB to operate the S4 OMP's actuator rod.

If the OMP is a concern to you, you'll need to switch over to an S4 front cover to use the mechanical S4 OMP, since the S4 ECU has no way to run the S5's electronic OMP. Or you could just block it off and premix.

I'm still kind of unsure which clutch to use if you have an S5 engine and S4 trans, I think the clutch has to match the engine series, but I'm not 100% on that.

I'm planning on doing the same swap soon, so I've been researching alot. The above is what I've gathered thus far.