Does the head have to come off to replace the camshaft in a 1990 Honda Accord? Also If I were to do this would port polish, or having the head shaved do me any good or just waste money? I am adding the h23 IM, the a6 cam to my car. I already have I/H/E, I am trying to gain just a little hp. I forget to mention this is on a f22a1 engine, any advice would be great!

 

Shaving the head will get you a few more ponies from the increase in mechanical compression. It may force you to move to a higher octain fuel and will require you to get an adjustable cam belt gear.
Why?
Shaving the head effectively moves the cam center-line closer to the crankshaft center-line. This effectively makes the timing belt too long. You need the adjustable gear to re-phase the camshaft.
Replacing the camshaft can be performed w/out removing the head. However, I'd suggest taking this opportunity to remove the head and refresh everything.
Unless the engine is going to consistantly see 6k rpm, gains from porting the head won't be felt by a dyno-butt.

P

 

Dang haha. i was gonna reply to this but had to step away for a moment and when i got back it was already pretty much answered. haha oh well