12-inch by 45-fin: '58-'64/'65, full-size. '64 seems to be when they made the change. I've done a BUNCH of research on this. Guys from the Buick Club of America were good enough to check their cars for me, and some said they had NOS drums to back it up. From '65-'71 or so, full-sized Buicks WITH OUT front disc brakes, came with 90-fin drums. -Brad
It should, unless someone messed with it. I got a set to the U-pull-it a while back from a '63 Riviera. That wasn't bad, for my $20 I threw them at eBay (was before I came here) and got $100 for them.
Yeah, the smaller 9.5-inch rear drums were finned aluminum, and came on a ton of things, from S10 Jimmys and Blazers to Camaros, Regals and Monte Carlos. I've also got four 9.5-inch fronts with a funky bell shape to them, that came off '67-'69 Buick Skylarks and GS. -Brad
I have been told that Buick increased the fin count to 90 for improved cooling....so in that respect........the 90's would be better. BUT.........most rodders want the 45 Fin........for the LOOKS....... and they bring more money $$$ and are more difficult to find.....
So the looks and tradition are the only reasons to use 45-fin in your hot rod, right??!! 90-fin will fit into Ford backing plates, right??!! Why don't they use 90-fin??!! I like them!!
My only thought about why 45 vs. 90 fins would be this: The first guy to make the swap could have done it in '58. The conversion could have been done with the 45 fin drums through '63/'64--the era of "traditional" rods. After that, they could have used the 90 fin drums, but it's not "trad" (god I hate that word) as far as the fantasy of building a 392-powered highboy in '59 goes. The dimensions of the 45 and 90 fin drums are the same, so with the same modifications you can put the 90 fin drums on your car. But that'd put the fantasy period as post-'63. -Brad
when i fell over a pair of 45 finned buick drums + 39 lincoln brakes it kinda pulled my 1928 pickup from being focused in 1952-1955 era into 1958, ahwell what ever its 2005 now so and 1958 was a good year...