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Poor braking due to cam

 
tzz281970
I love my Chevy Chevette!
Posts: 2
Joined: 08/13
Posted: 08/17/13 12:01 AM

Looking for a good solution to an age old problem, I'm running a 6.52 lift full roller cam in a chevy small block 406 ci with a victor "E" intake and a 750 mechanical double pumper in a 1970 camaro with original disk brakes in the front and drums in the back. Does anybody have a good solution besides a vacum tank that would give me back my power brakes?  

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waynep712222
I have an SS396 tatoo
Posts: 251
Joined: 03/13
Posted: 08/17/13 01:07 AM

a vacuum pump..

there are several kinds on GM cars .. mid 80s front wheel drive...

there are vacuum pumps hidden down infront of the left front tire.. up in the inner fender...

there are 2 kinds..  one with a vacuum switch on the pump its self.. another that uses a vacuum switch directly on the face of the power brake booster..

both require  one of the black fuel filter devices in the line between these booster pumps and the manifold vacuum connection .. the black filter devices are actually carbon canisters to absorb fuel vapors and prevent them from ruining the vacuum pump diaphragm and from ruining the power brake booster diaphragm..  you can stash these electric vacuum booster pumps out of sight.. up inside the fender. behind the hood hinge..  there is also special vacuum hose to hook these up.. usually 11/32 power brake booster hose..

you also have the choice nowadays.. to go to power steering pump hydroboost..

or self contained hydroboost...

http://www.chevyhiperformance.com/sch/02/hydroboost/photos/?SearchSource=Group

it may also be possible to go to a larger diameter booster since you are running a small block..  or a dual diaphragm version..  

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tzz281970
I love my Chevy Chevette!
Posts: 2
Joined: 08/13
Posted: 08/17/13 10:33 AM

Thank you very much Waynep, I'm definitely gonna look into that. The hydro boost solution seems like a good idea cause this way i don't have rob any vacuum from the engine. My car has been a "trailer Biatch" show car since 1989 with only 200 miles on it since, so i didn't have to worry too much about braking but now i wanna put her on the street and actually enjoy driving it but with out worrying about smashing into a tree or possibly hurting someone...i'm gonna start working on it this winter cause i have a few more things to do it before she's ready to go back out...i'll let you know how it goes when the time comes.  

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waynep712222
I have an SS396 tatoo
Posts: 251
Joined: 03/13
Posted: 08/17/13 11:47 AM

i hope that you get this..

by the way... because you still have drums in the rear.. and you might have mis matched sized tires..

big ones in the back.. small narrow ones in the front..  if you have this.. you will want to examine your stopping power with friends and a video camera on high speed with some duct tape on the sidewalls..

see which set of tires skids first...  

for gm drum brakes there are various sizes of wheel cylinders available..

you can go larger on the rear wheel cylinders to increase brake bias to the rear

or

you can go smaller on the rear wheel cylinders to reduce brake bias to the rear.

the idea.. is in a panic stop.. you really want them all to skid starting at the same time..  on a decent paved road..

why skid at the same time.. . so at just below the panic skid you have max braking equal on all 4 tires

there are adjustable proportioning valves available to reduce rear braking ..

and all of this depends on tire sizes.. weight distribution of the car on the 4 tires..  and about 50 more things..  

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