hey there guys. So my friend and I at work began talking about compression ratios and power adders for some reason. He used to have a turbo IS300 and i of course just got my 04 Cobra. I'm COMPLETELY new to the power-adder scene and he is more experienced having tuned and worked on his IS300.
Now with that said we began talking about compression ratios, and *I* was under the impression that superchargers (and turbos) RAISE the compression of the motor at peak levels of operation, therefore i was arguing that a blower will increase the motors compression of lets say 8.5:1 to say 11.0 (for example).
HE was thinking i was out of my mind and that power-adders do not alter the compression at all.. His example is, take a motor with 10.5:1 compression, throw a blower on it, and the compression will still remain 10.5:1. and compression is not changed at all.
He was explaining to me that cars with blowers generally have lower compression because then you allow more adjustable boost to fill the cylinders. Where a car with a high compression engine only has so much room for boost. That i agreed on....
*I* am under the impression that blowers will increase the compression ratio of the engine because of the fact that you are forcing more air into the cylinders, more air/fuel mixture is being compressed per cylinder (in the quenching area) and therefore the compression ratio of the motor is now increased at its peak levels of operation due to the supercharger/turbocharger being installed. Please correct me if I'm wrong here...
But i need some of you more experienced techs or non-techs to either agree with me here, or educate me on power-adders and compression. Because i was pretty dam sure I was right, and my friend had me 2nd guessing myself now
Now with that said we began talking about compression ratios, and *I* was under the impression that superchargers (and turbos) RAISE the compression of the motor at peak levels of operation, therefore i was arguing that a blower will increase the motors compression of lets say 8.5:1 to say 11.0 (for example).
HE was thinking i was out of my mind and that power-adders do not alter the compression at all.. His example is, take a motor with 10.5:1 compression, throw a blower on it, and the compression will still remain 10.5:1. and compression is not changed at all.
He was explaining to me that cars with blowers generally have lower compression because then you allow more adjustable boost to fill the cylinders. Where a car with a high compression engine only has so much room for boost. That i agreed on....
*I* am under the impression that blowers will increase the compression ratio of the engine because of the fact that you are forcing more air into the cylinders, more air/fuel mixture is being compressed per cylinder (in the quenching area) and therefore the compression ratio of the motor is now increased at its peak levels of operation due to the supercharger/turbocharger being installed. Please correct me if I'm wrong here...
But i need some of you more experienced techs or non-techs to either agree with me here, or educate me on power-adders and compression. Because i was pretty dam sure I was right, and my friend had me 2nd guessing myself now