well my friend just bought an 89 rx7 N/A and the owner told us that it has an S4 shortblock. now, my question is does this affect performance in anyway? because when i drove his car , it would hesitate at around 7000RPM and it wont go up to 8000 like it should. is that because of the s4 shortblock?

 

hey omeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee

 

i dont think so.....i know the s5 motors had a higher compression than s4's.......but i dont think swapping block would cause the rpms to stop 1k before it should

 

Are you sure it's still running the S5 ECU???

No reason why the S4 shrot block won't go up to 8kRPM, so long as it's running the S5 ECU.

The power might be slightly down; I'd be surprised if it's like 5+hp difference?


-Ted

 

yea the car still has the S5 ECU evrything in the car is S5 except the shortblock

 

check the spark plugs....... i know when mine were shot, she had a tough time getting up to redline

 

yea well now his clutch is fried so we got bigger things to worry about. but one more question. if he takes the cats off will the 5/6th ports still work? his car is an S5