93+ is a newer casting than 91 (casting numbers go up to about 5 or 6, then start over). 95 is the same as 93,94 but without the ports for the air rail. You'd definitely rather have a 94 head over a 91.

-Rob

EDIT: good to see you still around James, its been a while since i saw your name in a post. welcome back my friend.

Last edited by RobG; 01/28/05 08:19 PM.