I was thinking about buying a car either a type s Z1 or a spec v what would be better to build and what gen of spec v would be best?

Type S what? What's a Z1 (since I know you're not talking about the BMW)?

uh....I'm assuming an RSX Type S with a K20Z1 from the FA Civic Si....

hell, if I had an S to begin with, I'd probably just keep the K20A2 and put a k24 block together for it...but that's me...and that's what I plan to put in the EP3 in time...about 11:1 CR and BC Stage 2 cams...upgrade the valvetrain and spin the ***** to around 8500...fun city.

The SpecV Has a weak engine in stock plat form, I find. When I used to work for a Nissan dealer in New Haven, Ct., a lot if them came in with broken cranks and cracked blocks or heads. You have to do a lot if you plan on building a 2.5l SpecV engine. Stock is o.k. if you don't severely beat on it. For more hp performance you might want to swap out and get a stronger engine for it. An SR20 or KA24... I'm not impressed with the 2.5l engine, even though it's great for daily use. I could be wrong but, I haven't seen too many 2.5s built up that could be reliable. Not yet, any way...