Im thinking of buying a s5 t2 and switching my engine out of my s4 t2 but i would rather not switch ecu's and harness thank you for your help

 

The harnesses are different. I am not sure exactly to what extent but there are some major differneces.

I know for a fact the fuel inj. connections are different along witht the BACV, the AFM and the connectors for the ECU is different as well. This could all be worked around if you are really dedicated to doing it but I doubt it would be worth the work

 

just run s5 injectors, s5 afm, and anything else that dont plug and play

 

The way I read it, you are just going to put the series 4 block into the series 5 and use all of the series 5 hardware. If this is correct, then yes, everything bolts on and works just fine.

You have slightly lower compression rotors in the S5 motor is the only difference.

 

Not to mention the crossover harness in the dash does not plug straight in - you need to cut and splice several wires, especially if you want the water temp gauge and wipers to work properly.


-Ted