i know i know, i used the search and i read some threads. but i always hear like 32740340 different things. i have a S5 thats all ****'D UP picked it up at a auction but motor.tranny and stuff are all CHERRY. well im thinking about swappin the s5 into my s4. cant i just swap the whole motor instead of just using the short block and puttin the s4 parts back on?? i mean i have everything, ecu. wiring harness. all that crap from a S5. majority of the times i always see YOU CAN ONLY USE THE SHORT BLOCK OF THE S5..and i just dont get it. can someone please explain this to me. cuz i just wanna swap the whole s5 motor in. i just dont wanna use the s5 short block. thanks for the help...if there is any

 

Oil metering pump system needs to be switched.
S4 cannot control the VDI on an S5.
It's a royal pain in ***...


-Ted

 

The easiest way to do this swap is to use: S5 short engine block, S5 intake manifold, S4 Front cover, S4 Injectors, S5 Fuel rails, and S4 Oil Metering Pump. Put all together and have fun.

In a nut shell: Pull the S5 engine. Remove the front cover and install the S4 front cover. Install the S4 oil metering pump and the S4 throttle body. Use the S4 wiring harness and S4 injectors.

 

he wants to use the s5 longblock with the s5 harness and ecu. thought i would clarify. this would be possible i believe, yes?

 

Very possible, not by any means an easy or quick task but if you are switching the entire ecu it's doable.

Peace,
Matt

 

The crossover harness plug in the dash will not fit.
You need to repin or custom splice all those wires yourself, if you go with the S5 engine, harness, and ECU.
Although this is the most favorable option to go with, the crossover plug is a royal pain in the ***.


-Ted

 

ohhh ok SO IT IS POSSIBLE just a PAIN IN THE ***...ok i understand now

 

can you use said harness from the s5 car and put it into the s4?

 

Yes, you can theoretically pull the crossover dash harness from the S5...but then that harness doesn't plug into everything else.
Mazda made things a pain in the *** on the model crossover in '88 to '89.
Basically NONE of the electrical connectors are the same on either chassis.
So are you going to end up pulling all the electrical wiring harnesses?
Now I think you get the picture...


-Ted

 

bleh. yeah i guess i should have expected something like that from the company that brought us the electric omp...

 

so is it worth just using the s5 block and stuff..or should i just get my s4 rebuilt and ported?? same ****?? or does the lighten rotors and stuff actually HELP??

 

The block is worth the lighter and higher compression ratio rotors.
Swap all the S4 stuff - a ported intake manifold makes about the same power as the S5 + VDI.
I would just get the S5 short block and swap all the manifold over.
Get rid of the E-OMP and pre-mix.


-Ted