i have been gathering parts for my slant six build. I've got my head work done shave .050 to raise compression bigger valve to breath better. oregon cam a little more aggressive than( ordered yesterday) cliffford headers, msd box. Now my question isthis I bought carter afb i was told come a 273 performance package. Thought it was a 450 cfm turned out to be a 650 or 750 cfm, So now I need a new carb I was wondering if a holley 390 or edelbrock 500 cfm? I really prefer the edelbrock for boly on and forget about it but500 cfm it a little big for street use with A SLANT 6. Thanks in advance.