ok, i know your not a fan of savages, but on the the savage-central forums, theres tons of threads and info on modding engines.

www.savage-central.com

and click the forums tab on the left, make an account and search your little heart out. there are quite a few experienced engine modders that use that forum, but i dont think theyll be willing to give out their "secrets"

but check it out, TONS of info on almost any subject you can think of.