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Installed chevy axles under my truck and need to upgrade my brake master to hydroboost. I have already removed the stock setup. I now have dana 60 front and 14 bolt rear running four wheel disc brakes.....is it easier to stick with under floor mount or swap to under dash setup...
....new to the group and looking forward to hearing your thoughts
Cheers!

That means installing a power steering pump with all of the associated brackets and pulley's. Are you also going to put power steering on? I have seen on here write ups for power steering so maybe do a search for power steering conversion.

I may do that search tomorrow since I may be interested in the power steering.

as with any brake conversion, consideration must be made for balance and proportion. often means keeping the master from the brake donor vehicle or finding a master with the same bore/stroke and residual pressure valve pressure(s). also pedal feel makes up a good portion of the overall characteristics of the vehicle. I like the look and feel of the stock "through the floor pedals" on the 37. I find my foot is always resting on the clutch pedal, hanging out in the dead zone ready for action. one reason I drive a m37 is because the hanging pedals in chevs,fords and internationals give me clutch knee. tried a buddy's 37 with hanging petals, right away I could feel the pressure building in my knee as I worked the brake on his truck: 454rocket auto with power steering hydro boost on the fire wall.....

now if you don't get clutch knee from hanging pedals the entire chev pedal box can be modified to fit behind the dash. allowing easy installation of the master, hydro boost and tilt column.

mounting the brakes under the cab can be a challenge if you plan on using the truck off road. the stock master is water tight and vents to the air cleaner elbow. your standard chev master has no such provision. another issue with mounting the master under the floor is the amount of flex on the cab mount. the cab mount should be reinforced.

a set up I have been considering is a dual single master (willwood with remote fill) and a balance bar under the cab with a beefed up cab mount. as im not into power brakes and balance between front and rear is key. such setup would also allow for easy conversion to disk/drum setup.
something like this :

Ive considered both under floor and firewall.... and I think for this application... a firewall mount would be a better choice. Ive already installed a LQ9 6.0 liter motor, which has the power streering pump already prepped for hydroboost.. I will install the ps box after I am done building the three link front suspension... this truck will see extreme 4wd use, so having the master under the floor is not ideal. I am needing to find a really nice and small setup to squeeze in there. I think I am going to have to modify the inside of the fender to make it fit. Just wondering if anyone else has hung there pedals under the dash and have any pics or ideas. It almost looks like the center of the booster will be overtop of the steering column. So maybe an offset brake pedal arm?

I will try getting you a pic of a late 70s chev pedal box installed with hydro boost.

Did you shorten Dana 60 in front? Did you use stock springs or custom. Have other questions. Please contact me.

I have been considering getting some disks up front, I saw the 1980 Chevy Master cyl. swap directions at Ugly Truckling. But what I want to know is, if I keep four wheel drums for now, would the MC swap help the braking or would it just be a safety improvement being a dual MC? I'm swapping my gears first and then deciding about the brakes.

http://www.uglytruckling.com/m37_master_cylinder.html#

I don't know that an MC swap by itself would offer much-you're still pushing fluid to the same components on each corner. If they're old and/or suspect, or out of adjustment, you'd not gain much of anything.
Gary

808morgan wrote:I have been considering getting some disks up front, I saw the 1980 Chevy Master cyl. swap directions at Ugly Truckling. But what I want to know is, if I keep four wheel drums for now, would the MC swap help the braking or would it just be a safety improvement being a dual MC? I'm swapping my gears first and then deciding about the brakes.

http://www.uglytruckling.com/m37_master_cylinder.html#

Hydraulics are hydraulics, It does not matter about brands or if it is brakes or tractor lift cylinders the principals are the same. You have a small or equal size piston in the master and wheel cylinders. If the pistons are equal in size then the amount of force you put on the piston in the master is exactly what the piston in the wheel cylinder exerts on the brakes. With disc brakes the caliper is substantially bigger than the piston in the master so in that case the master will have to travel further to push more fluid with its small piston to fill the larger area of the caliper but when it is full, ( which by the way s instant since disc brakes ride on the rotor and therefore do not have to close a gap like brake shoes) then the force on the pads is a lot higher since you have a small piston pushing fluid to a large piston. The magic of hydraulics. The key to the whole thing is that you have both ends of the system matched or otherwise you will have either a solid pedal with no travel and no pressure at the [ads or you will have far too much travel at the pedal and too much pressure at the pads. The extra pressure is usually not the problem, the pedal hitting the floor first is!

rickf wrote:

808morgan wrote:I have been considering getting some disks up front, I saw the 1980 Chevy Master cyl. swap directions at Ugly Truckling. But what I want to know is, if I keep four wheel drums for now, would the MC swap help the braking or would it just be a safety improvement being a dual MC? I'm swapping my gears first and then deciding about the brakes.

http://www.uglytruckling.com/m37_master_cylinder.html#

Hydraulics are hydraulics, It does not matter about brands or if it is brakes or tractor lift cylinders the principals are the same. You have a small or equal size piston in the master and wheel cylinders. If the pistons are equal in size then the amount of force you put on the piston in the master is exactly what the piston in the wheel cylinder exerts on the brakes. With disc brakes the caliper is substantially bigger than the piston in the master so in that case the master will have to travel further to push more fluid with its small piston to fill the larger area of the caliper but when it is full, ( which by the way s instant since disc brakes ride on the rotor and therefore do not have to close a gap like brake shoes) then the force on the pads is a lot higher since you have a small piston pushing fluid to a large piston. The magic of hydraulics. The key to the whole thing is that you have both ends of the system matched or otherwise you will have either a solid pedal with no travel and no pressure at the [ads or you will have far too much travel at the pedal and too much pressure at the pads. The extra pressure is usually not the problem, the pedal hitting the floor first is!

True, I guess the only benefit is a dual MS has a safety bonus. I'm going to keep my drums for now and try it out. I am going to put the power steering in because a lot of parking areas I will be going was kind of tough to manever in. I drove a truck with good drums and it seemed ok. I ordered 4.89 gears but I think I will try driving the truck to my usual places and see if I need to do that at all. I could get taller Michelin tires, I have power kings right now.