yea i'm new to this engine tech stuff i have a honda accord and just know about the basics like bolt ons stuff like that......what is compression, why is it import for ur compression to be low for turbo......and why is it bad when it's high....also what kinda products can i buy to lower my compression?????????????????????

 

when your engine spins the pistons move up and down. there is what is called a piston and it moves in a cylinder. the piston is like a little plunger when the piston moves up it reduces the space that air and fuel mixtire can occupy in the cylinder. that is the simplest definition of compression i can come up with.

lowering compression reduces the chances for detonation. detonation is uncotrollably high spikes in cylinder pressure that cause catastrophic engine damage. when you have high compression the possiblity for detonation already exists so by force feeding it more air you increase the risk of the motor detonating.

to lower compression you can use a thicker head gasket, change pistons, change heads, or get valves that have reliefs in them. for anyone that reads this i know pistons are generally refferd to as having reliefs but i have also seen valves with them too. those valves are also generally lighter because there is less material to them. anybody else have their .02 that they would like to add. or tear my post apart as it maybe.


[Modified by racerxadam, 3:58 AM 1/5/2002]

 

hey thanks a lot man....that helped a lot.............but also like in engines..when they give u specs...on compression it's like 10:1:3 something like that......is that they way it tells how high or low it is?


[Modified by New2HD, 6:13 PM 1/5/2002]

 

yeah. that number is called a compression ratio. it is the ratio of the volume of the cylinder at the bottom of its stroke versus the top of its stroke. engines can run anywhere from about 6:1 to 12.5:1 and be driven on the street. from about 6:1 up to 9:1 or 10:1 is turbo range. and anything above 12.5:1 is getting close to the edge of detonation.


[Modified by racerxadam, 10:35 AM 1/7/2002]