H22 is DOHC (Dual over head cam) Vtech engine and it puts out about 190-200 horsepower

H23 is DOHC non Vtech and puts out about 160 horses.

You can find just about any other info you want if you search on google or something.

oh yeah and here are the types of ludes it came with...

Prelude S: had some gay ass 120-130 horse power engine called the F something

Prelude Si: had the H23

Prelude SH: had the H22

And there are other types such as the H22 A2, A3 etc etc but those are just minor differences.