advancing camshaft

For you motor guys out there...how many degrees would you advance the cam to bring the max rpm from 8400 to 8000? My cams in at 103-104 right now? Need more bottom and mid range pulls real hard at 82on up never falls off right now? On another note i am running a 2inch super sucker and maybe i should take it off and go to my 1inch super sucker? Will that make that much difference? Any input would be appreciated! Thanks

Depends on what the cam is ground on.If it is ground on 106 then it needs to be degreed on 102.

Anyone got any thoughts to the spacers?