Well, I figured out that my car needs a lot more vacuum than its pulling currently, so Im going to run out and get a gauge shortly, but does anybody have cheap tips on increasing it. For some reason I get the notion that its important to stop, and this would help out. Thanks for any help guys!
Extra Vacuum to supply your brake booster ? How about a large juice can (V-8) with a check valve to store it in. This should get you about 2-3 more good assisted pumps on the pedal each stop. Good luck ..H
Just so happens that some student in my shop class left a Vacuum reserve in there and hes already graduated last year, so Thats good, but Im looking for a way to produce more because not having enough can get scary. Specially when your expecting to stop with some ease and you come up about an inch short of a 2005 Porche GT...
If the reason you don't have enough vacuum is a cam that's a little too radical, Rhodes lifters will make a difference. My 283 went from 12 in to 16 with a change to those.
www.summitracing.com put SUM-G1464 into the search. i have a ridiculous cam and power brakes,that's what i'm using.
Thanks for the tips guys, should clarified this earlier. Its a completely factory 352 (with the exception of someone putting on a 2bbl manifold in the 70's gas chrisis). And Im working on a high school budget, so if worst comes to worst and I need to run with the Rhodes lifters I suppose I could scrounge it together, but Id like to see some other alternatives first as I think im gonna need that money on a beefed up alternater.
That motor should produce more than enough vacumn. How much vacumn do you have? What are you running for a booster?
Some of those old Chevy Cavaliers and clones had an electric vacuum pump hidden in the left front fender. Some diesels have a belt driven one. I am sure other cars had electric ones. How about one of those electric brake boosters, oh yeah you said cheap.
Assuming you don't have a burnt valve or something mechanically wrong, how about limiting the mecanical advance in your distributor and running about 15 degrees initial timing instead of the 4 or so reccommended degrees? Also, if you're lucky enough to have solid lifters you can loosen the valve adjustment a few thousandths. But, i agree that this engine should make ample vacuum. If they put a 2BBL on it, it sure shouldn't have some vacuum killing camshaft. A worn timing chain will retard cam timing and also kill vacuum. Good luck, and let us know if any of this works for you.
These cars used an electric vacuum pump. Buick 82 Skyhawk-J 82- 85 Skylark-X Pontiac 85-86 6000 82 J2000 82-84 Phoenix-X Chevrolet 84-86 Celebrity-A 82 Caprice-B 82 Cavalier-J 82-85 Citation-X Cadillac 82 Cimmaron Oldsmobile 86 Cierra-A 82 Firenza-J 82-84 Omega-X You'll find these pumps in front of the driver's side front fender well. Look for the vacuum lines running along the fender from the brake booster. Get the electrical plug that goes to the pump and the rubber mounting plate. The pump is also available new from GM. Various GM part numbers for vacuum pumps are 22062562, 22034995, 24505066, 10090521. Power connections are easy. Black is ground. Red wire goes to a hot source. Black with white stripe goes to switched power. Either the accessory side of the ignition switch or to a manual switch so that the pump can be run during cool down in the pits. The pump is powered via the A connection, but will only run if it receives power from the ignition switch on the B connection. Connection A (Red wire) battery positive, 12 volts+ through a fuse. Connection B (Black with white stripe) ignition positive, 12 volts+ Connection C (plugged) not used (not used in factory system either) Connection D (Black wire) ground, 12 volts- The junkyards should be full of them.
Thanks Steve M. I came across some places selling these, but I couldnt justify the $250 they were asking. Looks like a trip to the pick your part is in line.
Find out WHY you have bad vacuum, before you get the electric pump. You may be masking the problem, instead of FIXING it!
What kind of booster are you running (stock, aftermarket)? I have one of the small ones under the floor like this: I'm pulling 17 in lbs of vacuum and I have a second vacuum canister, and I still have a hard pedal!
Hard pedal, no air in the lines, not a bit mushy = good. Hard to push enough to stop and/or mushy, air in the lines pedal = bad. Which one you talking about? I'm running a '84 Mustang 7" booster, Me-made underfloor brake pedal assembly, similar to the one pictured above, with ECI kit Chevelle discs front GM 10 bolt drum rear and it's a one-toe-stops-it brake. If you aren't getting enough vacuum out of a stock engine I'd suspect the same culprit as if it had a really hot cam timing overlap, the cam. Possibly a stretched out or even jumped a tooth timing chain will give you lousy vacuum. If that's all in order, the M/C pushrod might not be adjusted right or the booster plain don't work. Way to check is to block the vacuum source all together and see if there's any change at all in braking. If not, the booster isn't boosting.
Or... you need a proportioning valve because your rear brakes are filling up and stopping the pedal before your fronts are fully engaged.
17 lbs is healthy. You have a braking problem of a different sort. What kind of car and what arrangement of braking componants do you have? It's time to inspect the system and make sure everything is working correctly.
you can also get a one way check valve in your line to the booster, the Volkswagens have these here at work cause of the turbos, ya know they create boost, the oposite of vacuum.
To answer a few more questions, Im running a dual resivour MC with an 8" dual diaphram booster. All of these parts are brand new and so im not sure as to what the problem is. Im not getting 17" of vacuum. Also, my car was fine with vacuum until after It had been re-wired. during that time the brake booster took a dump as well. Everyone I knew thought that they were directly related (the booster had a leak?), but as it turns out thats not the case.
Oops, pardon me Colorado51 is running 17 inches. How much are you running at the intake manifold where boosters normally are plumbed?
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