Hi, Have a friend with a 69 Impala with manual drum brake's and he wants to make it power drum brakes. We can find plenty of places that will sell booster's but no one can tell us if it is a conversion. Anyone done this already? The car only has 40k original miles and he dosent want to go to disc. Thanks
Your car is unique in that GM didn't make a special disc brake for your car they instead adapted a rear Corvette disc brake rotor to fit the front spindle of your car using a custom aluminum hub that bolts onto the Corvette rotor. They made these as an option for only three years and parts are scare as hens teeth. Expect to pay through the nose for these rare factory original parts.
You can buy kits from most aftermarket brake retailers to fit your car. They all rely upon a custom one of a kind home made steering knuckle or some kind of an adapter to bolt on a smaller Chevelle's disc brakes onto your car with an added down side of causing your front track to grow wider. This in turn causes a wide tire-wheel combination to rub the fenders. Not to mention the custom price they are going to charge you for the service.
Dave, You might have misread Mike's post a bit, he is looking for a drum brake vacuum booster not anything to do with disks.
Most of the guys at the parts store will have no clue what to sell you. I took a look at the part numbers and it is a bit diffucult to sort out becuase they made both Bendix and Moraine brake cylinders and boosters. You should have a matched set of booster/master cyl.
Also you have to be cautious because the disc brake master and booster are different than the drum brake master and booster.
The numbers (I think) you are looking for are 5469397 if you have a Moraine system and 3958996 if you have the Bendix brakes.
BUT most parts places can't cross reference GM numbers like these.
If it was me I would try and get a booster/master cylinder combo from a bone yard and rebuild them. Then you would be sure that you had them correct.
Or give one of the experts a call. Try Steve, he might just have one in stock. I've used him before to rebuild my original brake booster.
Once again I was "Shooting from the Lip". Talking before brain was fully engaged in gear. I can say (in addition to sorry for the confussion) that you want your used brake parts to come from the Desert Southwest because brake fluid is hydroscopic (it absorbes water). If you got parts from almost any where east of the Mississippi there is enough humidity in the air for the master cylinder to be a pitted pile of rust that will have to be sleeved to repair, as a simple hone job weon't clean it up.
Delco-Moraine I do not believe is still in business since GM's restructuring. Bendix is still very much alive and well and is what the parts counter guy will hand you as a replacement part if you buy something made under the NAFTA treaty (allows hecho en Mexico parts to be stamped Made in USA, though I believe most Bendix parts come from Canada). You realy want to avoid imported brake parts because brakes are important. Save the made in India or China stuf for bling like a chromed air cleaner.
Thanks Craig and Dave, I'm with you as far as getting a used assembly, But I don't know what year/make/model range I can work with. Is it 69 Impala only, or for sake of conversation, 67 to 78 GM brand? Will one off a Firebird or Chevelle work? My friend has been spoiled by power brakes but dosent want to change too much on the car. Thanks
Your 1969 model is part of a series of cars made from 1965-'70. Some parts interchange over a wider range of years (and some are 1969-'70 only; such as the disc brakes used by the factory). I will wager that your power brake master cylinder would probably interchange up through 1974, when GM again made a number of design changes to the suspension system (but I have no idea and recommend consulting an old Bendix catalog to verify what fits).
I agree with Dave here. One of the issues with interchange of the boosters is that many of the brackets (attached to the booster) are specific to the model. The firewalls were different and therfore even if the booster internals are the same they will not mount correctly on your firewall.
I am not positive but whn I was looking up the 69 full sze numbers it also listed the Camaro. Ths would only apply to manual brakes as the disc brakes are a whole different animal (as Dave pointed out above).
So you might get lucky with the '69 and be able to use Camaro drum brake booster/master BUT I would verify this first. I think one of the booster restorers might be able to help you on this one.