Thread: brakes are slowing me down

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This problem is slowing down my project. My recent engine swap has neccesitated in relocating the brake servo. The origional setup was a rather large linkeage from the brake pedal to the master cylinder which was part of the servo as one unit.
After a bit of a search in the scrapyard i found a nice remote servo which should do the trick as i have room to mount the master cylinder near the brake pedal and the servo can be hidden away neatly.
However, the car that i am taking it off is a bigger engine than mine- should i be worried about mismatching servos? Will it be benificial to have a bigger servo? Anything else i should know before i dive in?

sled

fred flinstone it

What kind of car?
By 'servo', do you mean teh power booster (vacuum booster?)?
Or do you mean teh proportioning valve, or perhaps something else?

Lol! okay, let me have a go at translating my origional message. Here goes:

Dayum power booster needs a'swappin cos i fitted one o' dem dere big engines and now it aint a' fittin no more.
Da stock power booster operated through one o' dem dere linkages an had da dayum master cylinder built inta the whole thang.
I got me one o' dem dere reeemote power boosters wit da master cylinder seperate so's i cayun hide da power booster outa da way, but da summbitch is off an automobile wit a bigger cc ( by about 100bhp) so should aaa be all in a tizzy over mismatchin' bigger brake components?

Asuming the 'Dukes Of Hazzard' is an accurate representation of American dialect i reckon that should be crystal to ya!!
But seriously brakes are a bit of an entity to me and its something i wanna get right so i just need to know if its okay to swap the 'power booster' to a bigger one than my origional disks n pads were designed to work with. Heaven forbid Robin Hood should gallop infront of me and im unable to stop....

I am guessing here but is the servo the master cylinder that supplies the hydrulic(sp) pressure to the wheel cylinders? If that is the case then power boost(vacum or otherwise) makes no difference. What you have to look at is the bore of the master cylinder in ratio to the wheel cylinders. If you are operating drum brakes at all wheels then try for a 1:1 ratio. For disc brake setups try for a 1:2. ie drums 1"bore master 1" wheel cylinders, disc 1" master cylinder to 2" caliper piston. In a disc/drum setup you will need a proportioning(sp) valve that came with a similar wheel cylinder/caliper bore combination. The next ting to consider is the pedal ratio. Try Wilwood brakes' web site for an explainationof that, it isn't hard but it is involved. I am assuming that you want about a 75lbs pedal pressure. Another option would be aftermarket master cylinders. I am running a CNC dual master setup on my 63 Scout and have been very pleased with the results. Happy Hot Rodding.

Sled, you need some of those diamond brakes that Head has!

If a servo is a vacuum booster, or a vacuum cylinder, to allow you to put more pressure on the brakes with less foot pressure, then a bigger one will not hurt anything. If it actually fits your master cylinder you'll be in luck. Whether you have disc or drum it won't matter because the power booster is first in the line, and everything else stays the same.

I've seen setups that turn the whole setup to a right angle under the dash. A bellcrank is then attached to the brake rod. Everything is then hidden, and I'm sure much more fun to work on. It shouldn't be that hard to build one, but they are for sale at different hot rod shops.