changing the compression ratios

[PatronZX]

Whatsup guys, i just want to know about how does shaving parts of an engine change the compression ratio. I've heard that shaving the piston lowers the compression, but shaving the head increases the compression. I mean when the head is shaved, how does lowering the valves and spark plugs closer to the piston increase the compression ratio? can someone please explain

 

[SLEEPER]

presuming this is a serious post ..................

Yes shaving pistons would lower the cr as shaving the head will increase it. This is becuse one decreases the combustion volume and one increases it

Most likely result of shaving engine bite though is that they will seriously shave your wallet cos if it isnt done by a real expert you wont have an engine to shave

 

[BAD63R]

If the head is skimmed and the valves and sparkplugs etc are closer to the piston, it ups the compression diue to the same amount of cumbustion but in a smaller area so you get higher compression ratio.

Alot of tuning companies will recomend a slight head skim with a steel gasket to boot, to up the compression/power on a N/A car. And pretty much all turbo's apart from low pressure ones, have lower compression pistons to stop the head from blowing to pieces from too much pressure.

 

[PatronZX]

Thanks for clearing that up for me. FORCED INDUCTION all the way! but N/A engines are cool also.

 

[HDi fun]

Forced induction seems to be the new NA doesn't it. Ford's 1.0 litre Ecoboost is a fabulous engine and looks to be capable of startling fuel economy even in a Mondeo sized car.