exactly without the big words what does the lower/higher compression ratio do? how does it affect things? =P thanks

 

Compression = how much air is being forced into the engine.

High compression allows more fuel, meaning more power.
Low compression is the opposite.

High compression pistons are optimal for naturally aspirated engines, while low compression are good for turbo applications, since the turbo will be providing compression.

 

nice explaination...now

whats a good compression then?

sorry...

what does each number mean?

tC = 9:6:1
civic si = 11:0:1

which is better? so the tC is better to f/i ??

 

it's a simple ratio...dont you remember high school math?

tC compression is 9.6:1, meaning the air/fuel mixture is compressed 9.6 parts to one. basically meaning that the volume at the top of the stroke could fit into the volume at the bottom of the stroke 9.6 times.

its hard to say which is better, there are alot of variables. with the tC your starting with more displacement (volume) at 2.4 liters to the civics 2.0 liters. and if you plan to go forced induction, your gunna be able to boost the lower compression tC motor more because your adding compression by compressing the air with a turbo/supercharger. in stock form the honda motor is much better. but just remember the aged old saying...there is no replacement to displacement.

 

speaking of compression....i just did a compression test and got like a 190 on each...really dont no much about compression...i no as long as its consistent thats good...but is 190 what the tc should be?

 

ooo my apologies....it says 9.6:1

i thought it said 9 : 6 : 1

its nine point six!

 

well general rule i've learned over the years, is lower compressions ratio equals better for f/i, while high compression ratios equals better for NA. If you have ever seen a truly great turbo car pushing crazy amounts of power, they always have a compressions ratio of 8.5:1 or near that......i call it the golden ratio, haha.....