I have question on restoring the suspension- steering I would like to put airride, and rack and pinion steering use original motor upgrade to newer transmision. Would i be better off to update rearend to newer buick rearend? The body I can understand retired bodyman but I'm undecided on how the ideas on suspension would be. Looking for stock look and better handleing Thanks Robert
If you change the trans to a newer style (I am guessing an OD unit) You will need todo something with the rear as you now have an enclosed driveshaft/torquetube system. You will need to convert to a conventional open driveshaft. I am also assuming you will be looking to do something like a fourbar setup for the rear suspension? Updating to a later rearend would likely be your best choice (as opposed to converting your orig. unit to open drive-there are no 'kits' available to do so-this means you need to do some machine work etc). The newer rear would give you a little better parts availability. A 10 bolt 'corperate' rear out of a full size Roadmaster, Caprice, Olds etc would be a good choice. The last rear series of them can be found with posi units if you desire. Now the next question is do you want to restore the original front suspension or do the common MustangII style swap? (personally I would just keep the stock susp with a spring and swaybar upgrade).
I know a guy who used a '61? maybe 62 third member to convert his '59 to an open drive. I don't know if that works on a '57 though. You might be better off with finding a junkyard rear end from a 60s buick and just make new mounts. But if's youre going with air ride and maybe a 4 link when you'll have to redo all those mounts anyway.
I have also heard that the 61-62 center sections cn be used for an open drive line conversion. But if he needs to make all new mounts, it may be a better idea to use a rear with more parts availability. Something like a late 10 bolt or even a 12 bolt would likely give the option of a disc brake conversion for the rear also.
I totally agree with finding a new housing if he's gunna make new mounts anyway. When you can buy NEW posis for 60-70s Gm cars with gears for about $500 it's tempting to make the swap. Gears for 57-64 Pontiac and Olds cost $400 just for the gears! I spent over $800 just on the posi unit alone! I'll be pissed if I blow it!
I run 57-64 Olds/Pont rear in my '55 Buick. Although I am running a locker, I doubt if you will blow up a posi in a street car. Even a healthy drag car would be hard pressed to blow one up. Is the rear in your '59? if so you probably have the orig 29 spline axles, those posi carriers are really hard to find and expensive. The spider gears are the only real difference though. You might have been able to just swap a 31 spline Posi in and get the later 61(?)-up axles. But you are right on about cheaper parts such as a $500 posi with gears,etc for late model stuff. Sometimes you can get lucky and find a whole rear for about that much with a posi and gears. Then you just need to fab the mounting brackets and such.
