Question for Boost Gurus

[gagt17]

OK, can someone explain compression ratio to me? Is it a constant rating, or does it change under boost? Thanks for your help.:confused:

[Weem]

Compression ratio is the relationship between cylinder volume when the pistion is up to when the piston is down. If the volume when the piston is down is 9 times larger than when the piston is up, then you have 9:1 compression ratio. It does not change unless you change pistons.

[gagt17]

<----:tool:
Thanks, Weem... you cleared up my confusion:D