the only reason i personaly would run aluminum is for detonation resistance they only flow minute amounts more than a well ported set of D0VE heads so unless you are having problems with a little too much compression i wouldn't waste my money. i would subscribe to this sit and port my own heads http://www.reincarnation-automotive.com/ it's $25 plus a die grinder and a couple carbide bits and you are still comin in under the price of aluminum. just my $0.02