Hello everyone, I found a disk brake conversion kit a while back and ordered it this summer. It's from The Street Rod Manufacturing Co - www.tsmmfg.net They've been mentioned in these forums before. This is not a promotion or ad in anyway. I found the kit online, ordered, and paid. I'm excited there is someone making the kit and wanted to share. I started putting my kit on last weekend and make some videos. It's a pretty simple process. So far I have the brackets, disks, rotors and pads all installed. Part 1: Part 2: Part 3: I'm currently working on putting in the new dual MC and doing the plumbing. I probably won't do a video detailing that since it's a well covered topic already. Hope you enjoy! Greg
Hi Dave V- TSM recommends no larger than 1 1/8" MC bore. I got a '76 Corvette MC for non-power brakes from Rock Auto: RAYBESTOS MC36367. That's what lots of people were recommending around these forums for other brake swaps. I hope it's sufficient. It seems to be what they use in the off the shelf conversion kits. They say "Corvette Style" Master Cylinder. Greg
I have been thinking of going with that same disc kit for my 49 3600 and was wondering if I should be installing a power MC or just manual. I looked up the 76 Corvette and see that it uses 1" MC for manual or 1 1/8" for power. Found both sizes in power at Ecklers to fit our trucks for $350. Now the decision is which size do I need. I'd love to know how yours turns out with a Manual MC
I put disc brakes on the front of my '38 1 ton. I used a '51 1/2 ton axle because it has a larger kingpin. I used a 1 inch non-power master cylinder from NAPA.
Wayne 1938 1-Ton Farm Truck Stovebolt Gallery Forums 1989 Silverado 1996 Mustang GT convertible When I die, I hope she doesn't sell everything for what I told her I paid for it!
Hey DaveV, All the dual power MC conversion kits (that go in the stock location) I've seen say they only fit trucks with aftermarket automatic transmissions. I think I saw them on Brother's trucks and Jim Carter trucks. They also say for 1/2 ton, so I wasn't sure if it would fit a 1-ton. I assume it would since the stock MCs are the same. I found that kit you mentioned on Eckler's... looks good! If I decide to go with power brakes that looks like a winner assuming it would fit. -- Edit, just found the fitment guide, it says it fits a 3800. Actually you guys are right - the manual MC I got is a 1" bore. I remember going back and forth worrying about enough pressure vs the pedal stroke being too far. I'll post updates as I go! Thanks, Greg
I realize they say that it only fits with an auto trans. but I've found that it is because they are trying to keep the unit installed in its original location due to transmission crossmember interference if the unit was shifted rearward. I have a T5 without a trans crossmember so moving the MC asmy rearward is not an issue and I already have another hole in the floor for filling purposes. I'm sure this can all work if we can just figure out the right parts like proper MC bore size.
So do you know if those Eckler power MC kits fit on an all original truck? They don't mention anything about clearance issues or what kind of trans or cross member you should have. They look pretty compact. I do have dual exhaust pipes that make things a little tighter around the MC though.
They show that it is for 47-54 GM trucks. I'm sure it's going to move the MC rearward and it does have a small diameter booster. I also have dual exhaust but will not be an interference issue. The mounting bracket on this unit looks like you would maintain the original clutch/brake cross shaft asmy unlike other units that eliminate that to keep the MC in original location and only be able to use an auto trans.
Part of my concern with MC bore size is that I have a Dana 60 rear end which has 1 1/8" wheel cylinders. The Corvette MC that so many recommend was designed to be used with 3/4" rear wheel cylinders. Not sure how this will affect the operation of the rear brakes.
That was my concern too - wanted to make sure the rear drums (HO72 rear with original drums) would get enough fluid and pressure to operate. With the disk/drum prop valve, it biases to the front, so maybe it's enough for the rear brakes? Sounds like you haven't finished your conversion yet? Let us know how it works out.
I found residual valves put in line helped the brakes. 2 lb for the front discs and 10 lb for the rears.
Wayne 1938 1-Ton Farm Truck Stovebolt Gallery Forums 1989 Silverado 1996 Mustang GT convertible When I die, I hope she doesn't sell everything for what I told her I paid for it!
I haven't even purchased the kit yet or started the project. Still doing my research. I do already have a dual MC on my truck with external 10 psi residual valves for the drum brakes. Have to find out if the new MC will have built in residual valves. As soon as I can figure it all out I'm going to order everything needed and get started.
The residual values are a little confusing to me. I've read things that say wheel cylinders have them built in, and now Dave is saying some MCs have them built in. I thought the prop/combination valve provided that function as well, but I'm starting to think it doesn't. Are residual valves required for proper brake function? I'm getting the sense they aren't, or at least it varies depending on what you have. What's confusing to me on the TSM Mfg site is troubleshooting the brakes. THey make kits for all different vehicles, so I'm guessing the tech tips might be more specific to certain setups. https://www.tsmmfg.net/tech-tips.html Depending on what is happening, they tell you to add a value, or remove one. I guess some scenarios you can end up with 2 residual valves depending on your components and you'll need to remove one to keep the brakes from dragging.
I've never dealt with residual valves, so what do you guy think? Should I start with no valves and add them if the pedal travel is too far or spongy? Thanks, Greg
I'm still trying to figure it all out myself Greg. What I have learned over the years is that the residual valves are necessary on our old trucks that have the MC located on the frame being the same elevation as the wheel cylinders. They are located either in the MC or external of the MC to keep a slight pressure at the brakes otherwise the fluid would be allowed to gravity drain back to the MC thus requiring more peddle travel the next time the brakes are needed. I did need to install them when I converted my truck to a dual MC years ago. As far as my concern about MC bore size I think I'm going with the 1" power MC setup and rely on a Proportioning valve to adjust the flow to the rear brakes. Just need to find out if the new MC has the residual valves built in. Maybe If we had this topic in the "Driveline" forum we would have been getting more views and input from the experts.
Wayne 1938 1-Ton Farm Truck Stovebolt Gallery Forums 1989 Silverado 1996 Mustang GT convertible When I die, I hope she doesn't sell everything for what I told her I paid for it!
I have a 1950 3600 that I put disc in front and back. but with my setup I mounted the MC onthe fire wall and hung a new brake pedal. my rear set up came from lugnut4x4 he worked with me to get this done. now we did change to a flat bracket and moved it to the back side of the mounting flange. the front was a kit from ebay for 55-59. i did a few mods to make it work
Thanks for the info guys - good articles on the residual values. I re-read my prop valve information sheet that came with it, and being a valve for disk/drum it includes a 10lb residual valve for the rear. I think most of the aftermarket/conversion kit valves do, it makes sense since you have to choose disk/disk or disk/drum. I ordered it from Brother's trucks, but it's a POL (Performance Online) branded valve. MattJ- that's a nice looking setup. Where does the new brake pedal assembly mount? Looks like it might hang from the underside of the dash? No visible bolts for it in the firewall. Greg
Thanks for that link - I think I get how it mounts- firewall bolts are hidden by the booster, and it looks like it might brace against the underside of the dash possibly from the steering column bolts
I read the MP site and watched the video. MP says in no uncertain terms never to use a perportioning valve for the front brakes. On my 3800 pickup with stock brakes I believe the factory front-brake bias is too much. The front brakes wear much faster and worst of all, when loaded on snow, the front brakes often lock up under medium/hard braking so I have no steering. With my camper there is 6,000 lb on the rear axle and 3,200 on the front axle. I once bought an adjustable valve thinking I'd use it for the front brakes but I've been afraid to install it. On the old class 8 trucks I used to drive, when they had front brakes at all there was a switch on the dashboard to shut them off on on slippery roads. In later years but before anti-lock brakes that switch disappeared. After that I had to chain up one steer tire to have steering on bad ice conditions, not unusual in the mountains of the Northwest and BC. I'm traveling less in bad weather now but I'd still like to have the option to limit the front brakes.
1951 3800 1-ton "Earning its keep from the get-go" In the DITY Gallery 1962 261 (w/cam, Fenton headers, 2 carbs, MSD ign.), SM420 & Brown-Lipe 6231A 3spd aux. trans, stock axles & brakes. Owned since 1971.
I didn't watch their video but read about the different valves available and the combination valve which is a metering valve and proportioning valve to the rear automatically compensates for a difference in pressure applied as needed. I hope I interpreted it correctly.
Hey Tommy - On my truck, it seems like the braking is biased to the rear wheels. It has bigger drums in the rear than up front. I've never locked the fronts, but I had to stop hard once and even with a 1-ton pallet in the back and I locked up the rears. That was also when I had very old tires that seemed a bit hard. Who knows what was done on these things in their 70+ year life time. Someone may have messed with the brakes on your truck at some point to bias them front (or someone messed with mine to bias them rear, haha ) who knows!
