The motors in the latest J spec Rx-7's put out 280 Hp. So, exactly what is it that produces the higher power? I know they have better turbos. Is it that these turbos put out higher boost or what???

 

The engine is the same....but I think it was the combination of the intake and turbos...

http://www.rx7.net.nz/newrx7.htm

 

OK, I read the link and it says the turbos are more efficient because they generate more air flow. That suggests to me that the 280 Hp engine runs at higher boost then does our US spec version. Anyone know how high the boost level is??

 

ummm read alil further then or more carefully. It says that the boost is up from 0.62 bar to 0.74 bar

 

Also they flow better because of the Y-pipe. It comes with the "efini" y pipe that we have to buy.

 

the rx7 in japan dosent have a cat in the downpipe. there's most of the power right there.

the newer rx7s have a slightly different intake.

the turbos have a smaller impellar for it to spool faster and a bigger compressor to push a little more air.

 

OK, so with what amounts to a downpipe and more efficient turbos the max boost on the J spec jumps to 0.74 bar (10.7 psi) from 0.62 bar (US spec?) (9.0 psi).

 

a less restrictive intake and exhaust will cause a slight increase in boost... im sure that its programmed for the higher boost though

 

I agree. It appears as if the stock engine is capable of 280 hp without any reduction in reliability if you install a downpipe and upgrade the ECU.

 

"the rx7 in japan dosent have a cat in the downpipe. there's most of the power right there"

the 255hp jdm fd didn't have a dp cat either.