[williamskinner16]

I had a 1981 Buick regal with a 1973 buick 455. the only clearance problem I experienced was the passenger side valve cover hitting the heater-A/C box. I had to upgrade the radiator( blew the upper header tube right off) I replaced the two core with a four core radiator for a chevelle.

Any-way here is what my motor ended up with-Poston sage I remanufactured heads poston GS116 cam (very mild) a used edelbrock performer intake ( B4B are the ones you want mine wasen't) An HEI distributer from a 76 buick with high performance coil cap rotor and aftermarket advance springs and bushings along with the stock 4 pin ignition module) 8 mm wires and bosch platnum plugs. edelbrock 750cfm carb,holley "red" electric fuel pump crane cams version of rhoads style lifters( give less lift duration at low speeds full lift duration around 2500-3000rpm). I never did a thing to the bottom end aside from the oil pump modification(explained later)and had stock exhaust manifolds with 2 1/2"duals and thrush mufflers.

something to keep in mind the buicks used the old rope rear main seal. as long as it doesent leak I suppose that its fine, however if you do work on the lower end or have a leaking problem that you can get a newer type seal used by 76 caddilac 500cui for application purpose as it will work. another trick is on the heads the heat crossover holes can be plugged by a small freez plug(I forget the size,sorry). this will add some horsepower, but keep in mind if you live in a cold climate that it will take longer to warm up in winter.

my car Dident have the Ideal Buick 455 the compression was low and I could have gone with a bigger carb as it was.(buicks tend to like bigger cfm than normally recommended) if I was to alter the gear ratio I could have gone with a bigger cam. but Ill tell you that I had more than enough power and it was, amazing! you really dont need to do much to make some real torque! My advice dont go crazy with rpms these motors are truely muscle my mild motor would pull strong to 6000 RPM. I am suprised that the stock differential held up. and that would be something I think may pose a problem for you if you build a Buick 455 meant for bussiness.

P.s. stay away from the 76 motor the heads are poor.- and milodin makes a bottom plate for the oil pump gears. the reason that the oiling has a bad reputation is that the gears in stock form sit on an aluminum plate that becomes scored allowing oil pressure to be lost. my plate came from a kit sold through napa it also comes with a variety of presure bypass springs.

good luck, this combo of yours sounds fun.