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911nut 911nut is offline
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Join Date: May 2001
Location: Michigan
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Originally Posted by WinRice View Post
Not true, you have two types of compression, geometric which is the ratio of the the volume of the cylinder at BDC vs the volume at TDC. Then you have effective compression which is when the intake valve closes just past BDC and only the remaining volume gets compressed.
Ok, that makes sense.
Sounds like another reason to bump the static compression ratio. This is recommended for n/a engines when running cams with a lot of overlap too.
Maybe it's better to leave the stock cams in place and switch to a more efficient turbo like a Garrett GT35.
Paul B.
'91 964 Turbo
Port matched, SC cams, K27/K29 turbo, Roush Performance custom headers w/Tial MV-S dual wastegates, Rarlyl8 muffler, LWFW, GT2 clutch & PP, BL wur, factory RS shifter, RS mounts, FVD timing mod, Big Reds, - 210 lb
Old 01-31-2010, 06:18 AM
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