I have a question guys, Is there a big difference between a J-spec rx7 engine and a US spec rx7 engine? If so can you list it plz? thanks

 

nvm, i searched more n found the answer. Tho i haven't found 1 for this. If my engines j-spec and i have a a-spec ecu im gonna have issues right?

 

If you swap over the sensors and other electronics there shouldn't be any problems or issues.

 

you just need a usdm wiring harness

 

The sensors are all exactly the same. A jspec harness could be used, but it's too short anyway. The original NA us-spec engine management harness should be kept for all turbo swaps regardless of where the engine came from.

 

the intake plenum is differant on the s4 it has no idle stop screw and few other little things (t2)

 

i got a tII A-spec wiring harness, everything have is a spec but the engine is j-spec

 

how so?

 

How so to which statement? Using the NA EM harness? There are many threads on this, including this one: https://www.rx7club.com/2nd-gen-archive-72/s4-na-turbo-swap-details-813825/