I have a friend im going to see this weekend he has alot of buick brake drums.I would like to have some on my 30 coupe.What do i look for as far as years of 45 fin buick brake drums?
Do you have 12" juice brakes on your 30 now.?? If you don't, then you need them. Any 12" aluminum buick finned drum will work.
the smart money would be to buy the 90 fin drums since EVERYBODY seems to want 45s. Those 90 fin just got to be cheaper and do exactly the same thing.......... Ray
Yup, as simple as that sounds, that is it. If it is a 12" aluminum drum, it is a Buick, and it has 90, or 45 fins.
Be careful about de-lamination. They get corrosion between the aluminum and the iron and go egg shaped. I have seen them .200 out of round!! Just look for a white line at the junction. Big is bad. You need hubs?
If you can, take a brake drum mike with you. New ID is 12.000 and factory recommended max is 12.090. You can get by slightly bigger than that on a light car, but too much beyond that you will start to get shoe contact issues. If you are going to mount them on different hubs, you'll have to turn them after changing the hub, so keep that in mind. As already mentioned, delamination is a big issue - especially in arears that used winter road salt. The early ones used a ball type bearing and the latter ones a tapered bearing - only of concern if you want to use the Buick hubs with bearing adaptors. If so, you want the tapered bearing hubs.
Jmountainjr is correct in stating that the most important part of Buick brakes is the initial internal diameter of the drum surface. These start as 12" drums. As suggested take a brake internal caliper to determine the size. If the drum measures over 12.060 used by the time you reface it to a smooth useable surface you will be too big for the shoes or cut too deep into the steel lining and into the bonding divots which allow the alumiunum to show thru. If you dont have a brake gauge just take a piece of 2" wide sheet metal and mark out a lenght of 12-1/16" (12.062). You can just insert this in the diameter of the drum, if it drops in and wiggles around the drums are too big. If its tight across the diameter then they are useable. The next is to examine the junction of the steel surface to the aluminum case. If the drum has been setting outside and water has permeated betrween the two surfaces and frozen it will separate the brake surface from the drum or create an out of round brake.
Yep, 90's are cheap, disspate more heat, and tend to be in better shape used because they're newer parts. If you trim off every other fin you still get 45, or 30 if you leave every third. Then have them rebalanced. A 90 with a broken fin is usually free and can be reclaimed this way.
90 fin drums really don't look right on a traditional hot rod, but I suppose it depends what look you're going for. I don't know when exactly the 90 fins came into play, but all the traditional rides I see are sporting the 45's.
My 90 fins are marked with a 12.090 discard. I don't remember if the 45 finned ones are marked. They were made a lot beefier back then before they worried about weight for gas mileage.
To some extent...yes. On the other hand, if no one ever has an original idea or puts it to use, we are soon very stagnant. Traditional doesn't necessarily mean everybody does exactly the same thing.......only that a variety off things, or ways to do something that were popular in a period, are utilized in subsequent years.....often with evolutionary changes that improve on the original without losing the 'flavor' of it. In my opinion, of course.
A point that bears repeating about the Buick aluminum drums. Some are held to the hubs with rivets, some are not. On the ones without rivets, the lugs studs are swaged to the drum. You must cut the swage in order to push out the studs. If you don't, and you attempt to press out the hub, you risk cracking or breaking the drum, even if you fully support it from the back side. Ask me how I know.
No, actually being trad is about being yourself. Most fellas don't want the 90 fin drums to hang out where everyone can see them so there is a difference if profiling is your major concern. If its about performing then you would probably prefer the 90 fin drums. But in answer to the question you can tell a 45 finned aluminum drum by looking and counting. Look for Buicks built in the later '50s or earlier '60s if you are looking at cars to crawl under. I'm running 90s on the back of a fender car and leaving the 45s for the fellas that need to profile. This car is running 90s. Of course it isn't trad.
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