I will be purchasing Crower valves soon. My question is I don't understand the effects of oversized valves. Also what would be the impact if I installed oversized valves on a supercharged prelude?

 

oversized valves allow more open area for incoming air to enter a combustion chamber. Just make sure you have the seats opened for the larger valve, or else it really doesnt do anything, and would be a waste of money. If you go too much larger though, you have to replace the seat.

 

I learned a valuable lesson with oversized valves. If you ever have a timing belt failure they will kiss/touch each other! I learned this the hard way!

 

if your gonna get oversized valves, i would maybe recomend getting some ferrea ones over the crower.