Can someone tell me the trick to turning a '60 Chevy truck master cylinder, which is half brake, half hydraulic clutch, into a dual bowl master cylinder? I see several guys using them on their hot rods, and would like to do this as well.
Then you would need to cut the clutch pedal off and then where you cut it off weld to the brake pedal so that they both work in tandem
Are you certain that is what people are doing and not simply using them as designed and running hyd clutch linkage?
Another dual cylinder option would be the MGA, early MG Midget, and early AH Sprite Brake clutch master. They come in 7/8" or 3/4" bore versions. These work well under a floor. There is a taller reservoir available that holds several more ounces of fluid. The outlets are 3/8" fine thread and use a bubble flare or a banjo.
I use mine as intended with the pedal assembly from a 60 pickup. I've never heard of anyone using them for a dual circuit but I guess you could.
Why reinvent the wheel when dual masters are out there that can handle things like uneven adjustments front to rear as well as a loss of fluid in either circuits?
What type of pedals are you using? If you're using aftermarket hanging pedals, like the Ansen hanging pedal design, you have to swap the guts.
Is the brake master cylinder bore the same size as the clutch master cylinder bore? It would seem to me like the brake side should use a larger bore than the clutch side.
I haven't had one apart for 50 + years but am pretty sure that the only difference between brake and clutch sides is the check valve in the brake side. On the clutch side you don't use the check valve or the rubber donut washer that goes behind it.
Just to be clear, I’m using aftermarket Ansen style hanging pedals. I also purchased a Stock Dorman dual master/ Clutch. Being as I’m installing them in the original position ie Firewall mounted, Would they not already be the correct bore/internals in the correct location ? Or, did the original chevy truck have some mechanical pedal assembly that Criss crossed the brake pedal to the clutch bore, and vice a versa. Thanks for your replies.
I don’t understand why you need to swap the guts. I’m using hanging pedals Aftermarket ansen style. And a stock master/clutch cylinder. Are the not lined Up with the appropriate pedal. Ie. Clutch to left piston and brake to right piston?
The stock pedals had linkage that crossed over. So, your clutch pedal would be pushing on the brake side of the master and vice versa with a hanging pedal set up. Some masters will have the outlet portions labeled so you could see which side is which and it would make sense. Edit: it was late when I wrote that. So, to clarify further, aftermarket hanging pedals have a straight plunger rod from pedal to master, so the brake pedal plunger would push on the oem clutch side and vice versa. To remedy this, since the pressure proportions would be off, just swap the inner portions from side-to-side.
The brake side has a residual valve, to hold 10psi in the line, and the clutch side does not. That's the reason for swapping the internals. I went to an International that has 1" cylinders, does not require swapping any parts. Only minor drilling to fit in place of the Chevy unit.
Open a bleeder screw drive to the end of your driveway step on the brakes and tell me if your car stops. Dual reservoir master cylinders are designed to work in tandem, both circuits need to be sealed and free form air to work properly. think about it you have to bleed both circuits before you have a pedal. Yes, you can pump the pedal and build resistance, which is good in a low speed scenario like someone backing out in front in a parking lot. However, at highway speeds in an emergency situation with a catastrophic failure do you really believe you will be thinking clearly enough or have time to pump the brakes to avoid a crash? I had a failure with the master cylinder in my 53 Chevy at low speed. The master cylinder bore was worn, the piston cocked and jammed. I shut the key off with the car in gear to stop it! I rebuilt the stock master and have not had a lick of trouble.
If you loose a circuit on a dual circuit master you won’t have a normal pedal. Pedal will become low but still have enough travel left to activate the circuit that is still working. That’s if , and I mean if pedal ratio and ample travel before pedal hit’s the floor is factored in.
Ok guys. I installed the antenna style hanging pedals, then I swapped the innards on a 1960 Chevy truck style combination clutch/brake master cylinder. I installed a 1960 Chevy truck style Clutch slave cylinder. Bottom line, almost impossible to depress the clutch pedal. Can this be Fixed by having the clutch master cylinder bore size reduced to maybe 1/2 “? Also, who can do that ? Thanks
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