I have the xe-268 and 360 heads { I know wrong heads , bad advice from a crooked mechanic } on my 318 and would be better off with less cam and stock heads but I'm going to get a 410-426 stroker instead , if you really want to go down the 318 road I'll gladly sell you my top end complete with a stealth intake and eddy 600 electric choke carb , hows cam ,lifters, 360 heads with correct springs for cam installed,intake and carb for $1500 sound I got gouged over 2 grand canadian for the whole package installed . Heck I'll even through in a pair of tires that will let you do a burn out at 30 miles an hour