Thread: Compression Ratio on sr20ve

Hi i am unsure about if the sr20ve head is shaved 1mm shorter what will the compression be? Will 20v cams be able to work safely witout damaging valves pulling to 8000rpm with this mod?

~11.2:1

edit: sorry, it should be more like ~11.4:1

i dont know the compression ratio theres higher chance of hitting the valves at higher rpms but thats unlikely unless going pass 9000 rpms but with 20v cams you need springs and retainers becasue this have a higher lift and have a higher chance of valve float in high rpms
hope this helps

Shaved 1mm, I think you're going to need bigger valve reliefs on the pistons with 20v's especially if you planning on taking it high.

So what you guys are saying if i am to use the 20v cams pulling 8000rpm my stock springs would'nt cut it? As well shaving the head would incurr 11.2 : 1 CR?

i would recommened a titanium springs and retainers with 20v cams theres a higher chance of valve float in high rpms up to you