273/318 Offy Dual Four Barrel intake

Easy guys, MtThunder is correct as there is no difference in the mounting angle of the intake. The early 273 heads used 5/16 bolt holes and the angle of these were slightly different but the difference is taken up when you drill the holes for 3/8 later bolts. You need to use washers under the new 3/8 bolts or the bolt hex catch on the intake during torquing them down. Its no big deal. I ran a performer on a 65 A with the weird bolt size/angle and it sealed fine with washers, also ran one the other way, a Commando 273 4bbl on a later 318, just drilled the holes larger and use washers.