Avanti brake booster brackets, toggle mechanism

[grobb284]

I was recently looking at the Avanti brake booster brackets, and associated toggle mechanism. It is similar to an early '60's Chevy.

What was the purpose of this, other than perhaps to give the motor some clearance?

My problem is it is mechanically disadvantaged. It appears that the pedal effort is reduced by about half, and the travel doubled to the booster. It can't be a disc brake reason, the Chevy's have drums.

Is this someway of utilizing the same pedal as standard brakes, with it's strong mechanical advantage, and not have to redo the swing pedal setup?

Just curious as to why you would go to mechanic disadvantage, only to boost it.

In just a few years, GM went to direct booster actuation without the toggle, just angled everything outside the firewall up.






1963 Studebaker Avanti: C4 Corvette narrowed front/rear suspension, C5 13" calipers/rotors adapted to C4, Viper differential with Intrax 3.54 ratio (the snake has been charmed!), coil overs, stainless tubular frame, stainless chambered side exhaust, real magnesium wheels.
Here are two links for some pictures and information.
Slide Show
Magazine Article

[Alan]

Flex in the glass. Years ago I installed a Mico master cylinder in my 63 and got rid of the brackets and booster. Built a 3/8" steel plate to mount the master to and sandwich the glass. When I had someone inside to press down hard on the brakes the master would dance. Gave the brackets to Will Carroll recently.

[Thomas63R2]

Go back and measure, it is not a 2 to 1 ratio, its close to even. The offset bracket is all about packaging and clearance. Yes, you could make something modern that did away with all of that business, they had fewer choices in '63.

What you could also do that is needed is to make a stiffer firewall. Because on an Avanti when you really press hard on the brakes the whole firewall area flexes.

Thomas

Long time hot rodder
Packrat junk collector
'63 Avanti R2 4 speed

[Thomas63R2]

Okay, here is how you do away with all the Avanti linkage: http://www.studebaker-info.org/Avant...ntipbrake.html

Thomas

Long time hot rodder
Packrat junk collector
'63 Avanti R2 4 speed

[wcarroll@outrageous.net]

Just remember, anytime you move the mounting position of the pushrod along the brake pedal arm (as the author did in his mod) you effectively change the ratio.

Getting brakes to work is one thing, but getting the geometry, leverage, and balance right is kinda a whole different deal.

You don't want to just start cutting and drilling without taking some measurements and crunching some numbers first.


Thanks again Alan

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