Odd but I had to know if its been done in the past or...I searched but nothing similar to my question showed up. I just pulled the rear out of my 51 Mercury and and it was in there but condition unknown and the last owner cut the perches off of it. Getting to the point, after doing some reading on the swap rears I have a disc brake 8.5" from a 99 S-10 blazer that im going to put in it since its nearly the same exact width and specs. The front drum brake system is still all stock but in good shape and functioning. Im still running that stock master cylinder though. Can this be done? Am I going to run into issues or do I need to add anything such as proportioning valve or a dual manual master or power master/booster unit? Will I be OK with the the stock manual master on this setup or?
Vaguely possible. Not a good idea. Wait until you can afford discs, and a proper master cylinder and proportion valve.
Well, its a $550 upgrade on the front not including master kit, ****s but budget build doesnt allow for the upgrade as of now and since I know that rear brake are usually something like 30/70% on a standard brake system that it might still be possible. I have not yet found a drum brake rear end with the correct width to go into the car. I would like to keep it drum due to simplicity on the install and not having to worry about asking this question..
Put disc on the front no matter what you do on the rear. We did this on dad's 57 Chevy and havent regretted it once. It is well worth it. I will be putting disc on my 57 as soon as I get it home. Thats just my two cents worth.
Sell the disc rear, then head to Lombard Auto Wreckers, 640 E. St. Charles Rd. Lombard, IL, 60148, 1-800-433-8728, and get stock #CFC047. $200+tax. It is a S10 4x4 drum rear axle, with 3.42:1 rear gears. Should be under 30-miles from you. It is a little narrower that the disc one, but not by much. If you wanted an exact match, a rear from a 1964-1971 full size Ford ought to do the trick.
That's back ***ward of Detroit! It could be done, a porportioning valve I'd think would be needed since you need more braking on the front (that's why factorys did discs on the fronts only for years) and I suspect the stock might not be up to it. You would have to disable the stock residue valve in the master and put an inline one to the front at least. I'd put a disc,/drum duel master on hooked up backwards if I was going to try it. That said, I wouldn't do it. Too big a h***le with questionable results. Good idea to have brakes that work right. A Merc is big enough it shouldn't be that hard to find a rear, a 10 bolt out of Camaro/ Nova up thru the 80's will fit, common enough there got to some of those still around.
I was under the impression that your original rear was 61". My memory sometimes fails me. Might be worth double checking. All of the 4x4 S10 rears that I have worked with have been 58", except for the disc ones. Check the one that I listed. It should be 58". The yard ought to be able to measure it for you, to save you the trip. Just make sure that they measure from the drum face to the drum face, not to the backing plates.
Consider parking it until your budget allows for properly set up braking system. I don't know what you think about your own safety, but we're on the road with you. /2 cents
Calm down there buddy, there is way worse than a disc rear/drum front brake experimented vehicle on the road today. I didnt say I was going to do it, I'm looking for options and though and if it has been done.
I'm plenty calm. I offered advice. Take it or leave it. As for "way worse," if you know them, please remind them we're on the road too. I'm tired of getting plowed into by cars that are unsafe to drive.
Of course! I have a disc brake on the driver side of my rearend and a drum brake on the p***enger side. I no longer have to even turn the steering wheel when making a left turn! Just a quick tap on the brakes! However, those right turns are a total pain in the ***....
If you dont want to hear the answer, dont ask the question... With a normal Disk/Drum setup ( drums in the rear, where they belong ), you have a proportioning valve on the drums. The front brakes do most of the work, and the pressure to the rear is lowered to keep the rear wheels from locking up. If you put a proportioning valve on your front brakes you wiill end up with worse brakes than you have right now, because you make the brakes that do the most of the work do less. If you leave the P valve out the rear disks would do next to nothing ( so worse than the drums you took off as well.)
I have seen it done very successfully. Jag rear with disk brakes and straight axle with 50 Ford pickup drums.Still on the road.
I put disk on my '29 and had to buy spacers for the calipers to clear the steelies. I bought a differential that was ''rebuilt'' but not set up right. Has a howl. Back to drums when I change diffs. No issues with stopping, 53 ford front drums, 11'' rear disc, single piston floor mounted master cylinder.
It really matters not what style of brakes are on which end of a vehicle. What matters is their relative effectiveness that is going to work or cause problems. For instance, 12" Buick drums (or similar) on the front and a 9" or 10" disc brake with modest piston size calipers on the rear, might work great, even without a proportioning valve. The problem is, unless you are a competent engineer and prepared to do a lot of math, it's hard to know for sure in advance what will likely work. And a trial and error approach will get time consuming and expensive. What you have proposed MIGHT work quite well, most of the time. But throw in wet pavement and/or a panic stop, and you may be VERY surprised at the results. Not a good time and place to discovering the shortcomings! Swapping ends into oncoming traffic could make for a very bad day. Ray
You can out drums on the S-10 rear 4 wheel disc brakes are an option. Drums are redily available. I am sure that disc drum run with the discs on the back have has been done. I can imagine that it was a headache and maybe never ever got sorted out. That is not to say that it can't be sorted out but why go through the headache. Just go down to the local U pull it and remove the drums from any late GM. Swap em out and sell the discs for cash to address another problem on the car. By the way a disc drum setup can be run on a single reservoir master. I have changed out the masters on 2 of a friends that ran disc drum to a dual master. They ran fine for years with the single. One was a long mile Stude (average 20k annualy).
Just because you can do it don't necessarly make it smart!!! I used to ride a '57 Panhead that had a spool on the front with no brake. When I had to stop fast I just slid my *** back a little farther on the rear fender...but that didn't necessarly make it smart...
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