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Like wtf bro, if you have a piston that's doing 12:1 compression ratio, that's a calculation based on volume. If you compress the air with a compressor, that pressure ratio is factored into the cylinder with the piston at BDC. Where is the calculation for the effective compression ratio where boost is added to the compression ratio at TDC? It doesn't exist, it's a conspiracy man. I mean what is the functional relationship? Is it additive? 14 psi of boost = 2:1 compression ratio, and an engine with a 10:1 geometric compression ratio now has an effective 12:1 geometric compression ratio? That can't be right, because then it would just be easier to use an 12:1 piston and save all the turbo plumbing. Is it multiplicative? 10x2=20? So a 10:1 CR piston with a 2:1 compression ratio from a compressor would effectively have 20:1 compression ratio? Or is it some other non-linear function that can only be gleamed through experimentation?

Like wtf bro, if you have a piston that's doing 12:1 compression ratio, that's a calculation based on volume. If you compress the air with a compressor, that pressure ratio is factored into the cylinder with the piston at BDC. Where is the calculation for the effective compression ratio where boost is added to the compression ratio at TDC? It doesn't exist, it's a conspiracy man. I mean what is the functional relationship? Is it additive? 14 psi of boost = 2:1 compression ratio, and an engine with a 10:1 geometric compression ratio now has an effective 12:1 geometric compression ratio? That can't be right, because then it would just be easier to use an 12:1 piston and save all the turbo plumbing. Is it multiplicative? 10x2=20? So a 10:1 CR piston with a 2:1 compression ratio from a compressor would effectively have 20:1 compression ratio? Or is it some other non-linear function that can only be gleamed through experimentation?

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[–] • 0 pt

You know what I hate about ASE tests? It's all ancient tech, modern cars have little to do with anything in the certs.

[–] • 1 pt

Totally agreed, also people that test well don't always, or even often, make good techs and some great techs test like shit.

I got all my ASE fresh out of school with the minimal job requirements and 5 years later I would have laughed at how little I knew when I passed. In my opinion they got too involved in brand promotion.

Left the industry years ago, things may have changed. (?)