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Happy Thanksgiving!

I am in the process of rebuilding my '49 Chevy 3600 3/4-ton pick-up truck. I have retained the old style "huck" drum brakes and replaced all of the wheel cylinders. I have installed new stainless steel brake lines throughout. I was looking for an aftermarket master cylinder to replace the original master cylinder, but have not found one with an 1-1/8" bore. I was planning to stick with manual brakes for now unless there is a good power brake master cylinder setup that will mount in the apporoximate same location below the floor. I do not want a firewall-mounted unit. Any suggestions?

Thanks!
Dan M.

Rockauto claims to have them in 1 1/4" bore. Are you sure of the bore diam.?

Napa list it as 1 1/4 in. bore. Part #9220

My mistake... 1-1/4" bore is correct. Is there a master cylinder available other than the stock unit?

Why do you want something other than the stock unit?

There is a bracket available to convert to a dual master, and lots of possible masters that can be used with that bracket.

But on an otherwise stock system why do you want to change the master?

Hi -

The only real reason I have for a different master cylinder is to go with a more modern split chamber master cylinder. However, with stainless steel brake lines, I am not as concerned about a brake failure. Also, I have seen the brackets for a different master cylinder, but I understand they are for the 1/2-ton trucks only, not 3/4-ton.

Thanks!
Dan M.

They will work on 3/4 ton.
http://s729.photobucket.com/albums/...current=700R4withLokarShifterBracket.jpg

I put the power break cylinder kit from CPP on my 3/4 Ton. I did have to slightly modify a brace that came with it so I could bolt it to the frame, but other than that, it worked great! My engine doesn't pull that much vacuum, but it's still easier to stop than manuals were. Hope that helps.

I'm no brake expert, but most of the brake failures I've experienced came at the MC, slaves, or the flexible lines, not the hard brake lines. Dual cylinders are a smart upgrade IMO.

Stainless lines won't prevent brake failure alone.
Lotsa other things can go bad A smaller dia. master bore will
make braking easier if you don't have the power unit
If you do, the larger dia. works better.

Thanks Guys!

Now I just need some suggestions on brands and part numbers from reputable companies. I'm looking for either a dual chamber, manual only master cyliner or a vacuum-assist power brake master cylinder set-up.

Thanks,
Dan M.

You're looking to put this on a 3/4-ton pickup. I'd look first at 3/4-ton GM pickups in that short range of years where dual master was required but before disk brakes were standard.

That is going to be '67 or '68 through '70.

When I did my swap I used a master designed for power brakes but did not use a power booster. It has worked out just fine, though I do understand there are some design differences between power and non-power. I was trying to stay with a specific year and model of car in order to match my other brake parts, and my chosen car was not available with out power brakes.

Mine came from speedway, Aluminum dual 1"bore and I am well pleased. 910-31422 $84.00 They have the stock one for about $35

Thanks! That master cylinder looks like it will work well. Do you know if this will bolt on to the stock 3/4-ton frame bracket?

Thanks Again, Dan M.