These H23 vtec post crack me up, you might as well buy and swap either an H22a1 or H22a(type-s) It will save you a lot of money and heartache in the long run. I have a friend who has done it successfully, so he thought and the engine blew out within a year and a half. It wasn't even fast than my (stock at the time) Factory H22. CAUTION: ITS NOT WORTH IT!!! If you really really need an H23 vtec do this. Ditch the H23 buy an H22 and buy a bore or stroker kit. Walah u've got ur H23 Vtec. Enough of this already!