[Bryan99cvc]

I always hear about people doing them on 5th gen and CRX's i was just wondering if anyone had done this on a D16Y7 by swapping a Y8 head. I always hear that just doing the swap alone will net you more power then a stock EX, because of the higher compression with the Y7 block. Is this true, and ive been hearing numbers around 135-140 engine HP.

 

[aemcivic_02917]

ill let ya know how it goes using my old y7 bottom end in my brothers 99ex with his y8 head and his t3/t4e turbo... it will be intresting waiting on the new timing belt and water pump.

 

[klungemonger]

I always hear about people doing them on 5th gen and CRX's i was just wondering if anyone had done this on a D16Y7 by swapping a Y8 head. I always hear that just doing the swap alone will net you more power then a stock EX, because of the higher compression with the Y7 block. Is this true, and ive been hearing numbers around 135-140 engine HP.

That's an overstatement at best. You can get those kinds of gains on an A6 block but not a Y7. The compression gain is minimal, still not even 10:1 c/r. Take into account that the EX has slightly higher compression (9.6) than the Y7 (9.4), mainly due to a smaller combustion chamber. I used a compression calculator and figured around 9.8 c/r on a Y7 which is good for probably good for 130hp at the crank, but not 140. That's about 3hp more than the Y8 stock.