I am new to the scene so i need some advice. i have had this 90 integra gs with the 1.8 non vtech engine for the past 10 yrs now. i just replaced the engine about 6 month ago and i want to get some more power out of it. i have a k&n air intake on there and obx headers. i am thinking of having the head polish and bore, is that a good idea? and what kind of gain in horsepower should i expect if any? and how much bore should i ask for? and should i change the piston and rods to gsr or type r when i do this?
thank you very much for your help