boost ratrio

[hartwrenches]

how much does your compression raise compared to boost?
example 3 pounds boost takes 180psi compression to 190psi compression

I know the example is wrong, I just want to make it clear what I'm asking

 

[RacinNdrummin]

Well it depends on a lot of things.... but simply

((Boost pressure/14.7)x(stock compression))+Stock compression.... should get you close

 

[AllanD]

Huh???

How about:

(((Boost pressure x 0.7) + 14.7) / 14.7) X (Mechanical Compression ratio X 0.85) = Effective compression ratio

Boost pressure in PsiG

0.7 = 70% efficiency of a typical turbocharger NOT-intercooled
(they heat the air and lower the effective density)

14.7 Ambient Atmospheric pressure

0.85 = typical Ve of pushrod engines

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