Which compression would be best for a lsvtec turbo using a precision 57trim .63 3431e , log manifold, 3" dp and exhaust. B16 head port n polish gsr cams. The goal is around 400.whp a street car that hits the drags on the weekends. I have 3 pistons in mind the wiseco k541m815 which I think will yield 9.0cr, the wiseco k542m815 which will yield 9.8cr, or supertech p4-h815-n2 which will yield about 10.2 cr.



Thank you

 

Well, according to simple compression calculator :

wiseco k541m815 which I think will yield 9.0cr 8.66:1 ACTUAL

wiseco k542m815 which will yield 9.8cr 11.28:1 ACTUAL

supertech p4-h815-n2 which will yield about 10.2 cr ACTUAL 10.1:1


So I would go with the supertechs You should be sure of what the actual c/r is going to be b4 you make choices like this!

 

Agreed you def need to run the compression calculations before deciding. http://www.zealautowerks.com/bseries.html

Personally I would never build a street engine under 10:1 anymore. Many stock S2000s with 11:1 compression make excellent power on mild boost and pump gas. I would not be afraid of 11:1 compression with a well built, well tuned engine.