Hi I’m trying to add some hp to my stock h22 with 145,000 miles what should I do? Should I rebuild the motor if so top end and bottom?

 

just basic maintenance. its not really worth to drop several thousands into the engine just to get something like 25-30hp more out of it which you hardly even notice

 

Nitrous has the cheapest upfront cost and is by far the easiest to install. You get a lot for your money but you constantly have to be worried about filling the bottle and bottle pressure depending on how much you use it. Local availability can also be an issue.

NA requires at least $2k to make noticeable gains but would be the most reliable. Type-S pistons, Cams, springs/retainers, balance shaft delete, lightweight flywheel, good header with a 2.5 collector, 3" exhaust.

Turbo will easily be $4-5k getting your foot in the door. Stock H22s are not the most reliable engines when turbocharged either.