blowers/ turbo's

[poncholvr]

hey whats your compression with and with out your boost??
anyone done any readings like that?, before ,and after boost is applied?
-8:1 b4- 12 after??
curious is why i ask

[dak697]

((boost psi / 14.7) + 1) x motor compression = effective compression

this is the compression ratio including boost of a turbo/blower motor compared to a naturally aspirated (sp) motor

[kwkracing]

well if this calculator is right, my street car has 8 to1 before and 13.6 after 10 lbs and my dragster has 12.5 before and 25.5 after 15lbs?

[dak697]

pretty much

13.44

25.25

[zipper06]

AAAAHH!!,
I don't know about that? 358" SM/BLK 10.5 to 1, 1471 20% O.D. 30lbs boost, sounds to me like that should blow the crank out the bottom and the heads off the block, but it don't, and i know there's a couple other guys on here besides myself that run atleast that much boost with SM/BLKs sucessfully on alcohol.

JMO

Zip.

[feenst]

Using this I get pretty much the same numbers: http://www.wallaceracing.com/boost-compression-ratio-calc.php

[kwkracing]

zipper, your running 32 to 1 in a old sbc!!!! Lol!!!! Maybe we should weld our heads to the block!!! I AGREE. This formula can not be right, as the rpms increase you can not go by static compression to find actual compression at any gaven rpm.