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compression ratio increase

1149 Views 7 Replies 7 Participants Last post by  cheappower82
going from stock 8.8:1 to 10,10.5, or 11:1.

which one would be best? i know 11 offers more power but if i went that high would i be using octane booster? i'm thinking 10.5 like the new celicas run.

i want to do this by using a thinner headgasket and shaving the head.

anyone else done this for power? how did it turn out?

also thinking about a 3-angle valve-job and p&p while it's in there they'll only charge 100 more for it.
1 - 1 of 8 Posts
If you increase your compression and don't change the motor's breathing habits then you won't see much gain. Raising the compression isn't just a quick fix, for the best results you should tinker with the timing, intake temp., and fuel injector mapping. The injector pulse time doesn't need to be changed, but the pressure should be increased on stock injectors, if you're looking at 11:1 then I recommend you use larger injectors.

Of course, you'd run into more issues as well but I won't get into all of that. Unless you feel like putting several hours into perfect tuning then don't go up by more than 1 point of compression.
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