Ive been thinking about putting high compression pistons into my car and possibly boring out the engine to about a 2.2 or 2.3 liter. If i were to just put in new pistons what else would i have to do? What kind of performance can i expect? If I would also bore out the engine would it be worth it and what all would i have to do for boring and high compression pistons?

4% gain in hp per point of compression. So if you go from 9.6 to 10.6 then you'd gain like 5.6 hp.


On a side note, you can't bore out the 420a to 2.2 or 2.3. You can stroke it close to 2.2.