If I change the compression on my K20A base block to 12.5.1, would be as powerful as the K20A Type R block which has 11.5.1 compression?

 

What do you mean by k20a base block? LIke k20a3?

Do you have a vtec head?

Rule of thumb, when you jump 1 whole compression point, that should be around 10HP increase if everything is done right.

 

No, a K20A3 doesn't have enough camshaft for 12.5:1 compression. You will pick up some power over a stock K20A3, but you need more aggressive cams to go with the increased compression to really make power. You will need a way to tune the engine... like KPro or something similar. The good news is that if you build it right, you CAN make a K20A3 base engine make more power than a JDM K20A Type R engine.