Why does the rwd sr20de make 165hp stock and the fwd sr20 only makes 140hp? What are the differences with each motor? because I can use 25 horses if you ask me. In my opinion thats how much power a sr should have came with anyhow the h boyz would take us a little more seriously.

I would think that it's all in the head.

rwd sr20 has always been faster...even though i have both rwd and fwd sr20s

I think the only RWD SR20DE to make over the typical 14X crank hp is the S14 with the VTC... and I don't think it's just going to bolt onto your FWD DE head. That's what the SR20VE is for ;)

FWIW, I have the S13 SR20DE and it did not feel fast at all. Besides the difference in the block (FWD/RWD), the interal parts are mostly all the same... I even measured the cams and they are identical to the 91 cams out of a FWD SR, go figure.

I was gonna say maybe because one is longitudinally mounted and the other is transversely mounted but, that doesn't make a difference because these ratings are at the crank.

pretty sure its tunning

rwd sr's are designed for jap fuel which is much higher octane than u.s. and aus fuel

same thing happened here as well with the s15....our sr20 only has like 147kws standard where as the jap model had 180 something...however the engines are pretty much identical, get a retune and the will match each other down the quater

Wikipedia to the rescue

http://en.wikipedia.org/wiki/Nissan_Silvia

snip and cut... The S14 and S15 SR20DE got VTC, hence the jump in hp.
...a slight bump in power due to the implementation of Nissan's variable valve timing system, VTC

because the piston are high compresion?? like someones jap fwd sr20de

Autech made a 165+hp fwd SR. I think it was 175 hp crank actually.