Cincinnati Rick

I bought a 3.08 anti-spin axle that was from a 71 or 72 V.C.to put under my 68-442-vert. I was told by a reputable axle rebuilder that I would need 9.5" x 2.5" drums for this unit. I ordered some brake pads and drums from a local auto parts store and received drums that were only about 2.4" wide on the inside finished surface. Any thoughts on where I might find the correct size drums? I've searched all the usual online parts places but haven't been able to find anything. The shoes I received seem to be correct but they are a smidge wider than the drum mating surface.

Loaded68W34

I might have the old set of drums from my vista on my shop floor. Nothing was wrong with them, just did not need them when I put the discs on the rear. If you get some pics for the areas you are measuring and what the measurements need to be I'll check if that is what they are from.
Tom

skyhigh

https://www.rockauto.com/en/catalog/...+hub,drum,1744

Cincinnati Rick

Thanks Tom...I'll take some pics this evening and post them.

Cincinnati Rick

I looked at those before I posted. Looks like they are 2" not 2.5"

joe_padavano

It sounds like the drums you got are either made wrong or are for a non-Vista axle. Correct Vista drums are Centric 123.62005 or Raybestos 2037R. The drum friction surface should be about 2.9" wide. RockAuto has both in stock.

Cincinnati Rick

Well I'll be dipped. I didn't pay close enough attention to the specs when I looked at both those part #'s on my original search. Thanks for the help Joe.

mpolds

Both of those options are of course, very Chineseum.....
I may be too late to the party, but I have *** two (2) last N.O.S. U.S.A. made *** Rear Brake Drums and *** N.O.S. Asbestos *** Brake Shoes for that same application.....

Always best to simply call me--- 516 - 485 - 1935 --- Craig......

Mr Shifty Sidney

Rick
Will the regular drums not work with that rear? I would be concerned about the rear brakes locking up prematurely with the bigger brakes??? Just a thought.

Don W

mpolds

I would think that putting the CORRECT parts on a vehicle would always be the CORRECT move....
the Vista Cruiser / Station Wagon received the 9 1/2" x 2 1/2" Rear Brake Drums and Rear Brake Shoes for a reason --- back in the day , Station Wagons were , of course, designed to carry extra weight / cargo / Extra passengers, etc., etc.....

I would think that it is ALWAYS CORRECT to use the CORRECT parts for any application, rather than
" think " what would happen with WRONG parts......

Loaded68W34

Except.... Cincinnati Rick is running the 71-72 vista rear end in a 1968 442 convertible not a vista cruiser.

joe_padavano

But he still has the Vista 9.5 x 2.5 rear brakes. The Vista backing plates are unique because of this.

Cincinnati Rick

Yes, the backing plates are backspaced to make up for the wider shoes.

mpolds

As Joe P. Points Out, naturally, that is what the rear end is --- that is what counts....
so, you do the math ........

Plus, I only have *** two (2) --- 1 lucky WINNER!!! , it's not like I have 100 ***,
If you / Cincinnati Rick are the WINNER --- GREAT !!!, If not , someone else will be.....

Craig.....

Loaded68W34

I realize the backing plates on the vista rear need the special shoes/ drums. However, in post #9 Shifty Sydney posed a question if running the larger vista brakes on the Rick's car would cause issues with the brakes locking up in the rear. The majority of the response in post #10 was not that the shoes and drums are needed for the rear backing plates but that they were needed because the "CORRECT BRAKES" made up for the added weight of the vista cruiser which Rick does not have. It would have been simple enough to say the extra braking force of the vista drums should not cause any problems in Rick's car (which should be the case), but the actual question from post #9 was never even addressed (simply large capitalized text that appeared to be calling Shifty Sydney out). I have absolutely no interest in your parts as my vista has a Chevy 12 bolt in it with 13-inch wilwood disc brakes and I got rid of the original rear years ago when I originally replaced it with a 10 bolt chevy rear to put on 98 camaro rear disc brakes (possibly still have the vista drums though). This is why I offered my old drums to Rick in post #2 if they are the ones that he needs. By the way Rick, that offer still stands. You can have my drums for the cost of shipping if they will work. Just need some pics to confirm measurements. PM me if you want them.

joe_padavano

This is exactly the right question. Unfortunately there is no easy answer. Front/rear brake force balance requirements depends on weight distribution, tire friction on the road surface, and obviously the details of the brake system. The factory balanced braking for each vehicle by selecting friction material, brake swept area, wheel cylinder size, and ultimately a prop valve for model years 1971-up. Note that unlike the one-size-fits-none combo valves that come with disc brake kits, Olds had specifically-calibrated combo valves for each application. Differences were in the sizing of the internal spring that set the front/rear line pressure ratio.

The Vista brakes are sized for the heavier wagon, and even then the final brake force selected by the factory was a compromise between empty and fully loaded with a trailer. VC's came with 1" wheel cylinders. Lesser Cutlii, even with the smaller rear brake swept area, came with 7/8" wheel cylinders on drum brake cars and 13/16" wheel cylinders on disc brake cars. This is for the 1967-70 cars that did not use a prop valve. For the 1971 cars where Olds did incorporate a proportioning feature in the combo valve, the same 7/8" wheel cylinders were used on both drum and disc brake cars (and 1" cylinders were still used on the Vista).

Bottom line is that when mixing and matching brakes, you probably want an adjustable prop valve so that you can dial in the front/rear balance for your specific weight distribution, tire selection, and brake hardware choice.

The other message, by the way, is that you really need to think about spending big bucks on a rear disc brake swap if all you plan to do is to dial back the effective brake force to the same as it was with the drums.