Anyone here know of a quiet vacuum booster motor?

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I've never used one, and have no recommendations for any, but Summit uses the term "quiet " a few times, even as av"quiet" alternative to other brands. Maybe you got a bad unit. Call Summit and return it. You don't have anything to lose.
 
B'cuda said:
I've never used one, and have no recommendations for any, but Summit uses the term "quiet " a few times, even as av"quiet" alternative to other brands. Maybe you got a bad unit. Call Summit and return it. You don't have anything to lose.
Click to expand...
Thanks but bought it 3 years ago , might be past return date .
Can't believe they rate this quiet , at least it works . Guess all I can do is change the cam or get lucky and find a quiet pump
thanks
 
Nat said:
I have one from Summit , trouble is it sounds like I have a baby crying in the trunk and it is loud . pump works but is driving me crazy
Just wondering if someone is using or knows of a quiet vacuum booster pump .
this is the one i have LEED Brakes Bandit Electric Vacuum Pump Kits VP001B




thanks
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Having same brake problem. Was 10 seconds from ordering the same pump not anymore thanks for the info. Will be watching to see about a quiet pump
 
Or just buy a 15/16” manual master cylinder and a manual brake rod and not worry about it ever again.
 
72bluNblu said:
Or just buy a 15/16” manual master cylinder and a manual brake rod and not worry about it ever again.
Click to expand...
Thinking about that only one question are the calipers and wheel cylinders the same for power and manual brakes
 
Ahoey said:
Thinking about that only one question are the calipers and wheel cylinders the same for power and manual brakes
Click to expand...

Everything is the same except for the master cylinder and the brake pedal rod.
 
72bluNblu said:
Or just buy a 15/16” manual master cylinder and a manual brake rod and not worry about it ever again.
Click to expand...
Can u tell me the length of the pushrod Chrysler Canada doesn’t have measurements on them and the part is obsolete
 
what's the problem? lol...

FWIW I ran the 292/292/108 cam in my 367 with booster from a 73 Dart. The only time it didn't work was at first start in the morning. (No fast-idle) A couple of blips of the throttle, and BadaBoom, she was in business.
 
Well this
AJ/FormS said:
what's the problem? lol...

FWIW I ran the 292/292/108 cam in my 367 with booster from a 73 Dart. The only time it didn't work was at first start in the morning. (No fast-idle) A couple of blips of the throttle, and BadaBoom, she was in business.
Click to expand...
one is in. 540 ex 561 lift 312/326 duration it make 6 inches of vacuum checked everywhere with spray no vacuum leaks maybe booster is fubar master cylinder is new
 
At what rpm does the vacuum pop up to 11/12?
My Dart booster requires about that to begin charging. It charges in a few seconds. Even on a long slow stop from whatever speed, that booster worked right down to near-stopped, at which time, it doesn't take much effort to brake as a manual.

Here's your test.
Shut off the pump.
Hook up your booster to the intake plenum; NOT an individual runner.
Make sure your vacuum checkvalve is working, get one that provides a vacuum tap on the booster side of the valve. Hook a vacuum gauge to the booster, that you can read from the cabin.
Pump your pedal a few times to empty the vacuum chamber.
Put some modest pressure on the pedal, and just maintain it, then start the engine.
When the booster comes on line, the pedal will began to fall under your foot.
Note the vacuum at which this begins.
If the pedal does not fall, rev the engine up to 10 inches vacuum, then 11 then 12 or until the pedal falls. That is your minimum vacuum for that booster.
>If the pedal does not fall, something is wrong. Either the booster is defective, or has an extremely high minimum vacuum requirement, or more likely, the pushrod length is too short.
But if it works right,
go for a drive and make note of how often and under what circumstances, your vacuum falls below the minimum.
If your check valve is working, the booster will continue to work, even if the engine stalls, for at least one long slow braketest.
Finally, put her in park, then charge yours up to whatever maximum vacuum your engine can achieve, then shut the engine off,. Do not touch the brake pedal. The booster should maintain the vacuum above the minimum, for several minutes.
>If it doesn't, something is wrong. It could be a faulty checkvalve, a faulty control valve, or a pedal not parking properly, which could point to a too-short pushrod.
Happy Hunting.
 
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Never used one, but!

Mounting could surely be an issue and on firm steel like a frame rail. Closer to the booster makes more sense to me. A trunk mount seems a little silly. If mounted through the pan to rear frame rail seems the best. Mounted on the floor pan alone seems Like an oil can to me.
 
AJ/FormS said:
At what rpm does the vacuum pop up to 11/12?
My Dart booster requires about that to begin charging. It charges in a few seconds. Even on a long slow stop from whatever speed, that booster worked right down to near-stopped, at which time, it doesn't take much effort to brake as a manual.

Here's your test.
Shut off the pump.
Hook up your booster to the intake plenum; NOT an individual runner.
Make sure your vacuum checkvalve is working, get one that provides a vacuum tap on the booster side of the valve. Hook a vacuum gauge to the booster, that you can read from the cabin.
Pump your pedal a few times to empty the vacuum chamber.
Put some modest pressure on the pedal, and just maintain it, then start the engine.
When the booster comes on line, the pedal will began to fall under your foot.
Note the vacuum at which this begins.
If the pedal does not fall, rev the engine up to 10 inches vacuum, then 11 then 12 or until the pedal falls. That is your minimum vacuum for that booster.
>If the pedal does not fall, something is wrong. Either the booster is defective, or has an extremely high minimum vacuum requirement, or more likely, the pushrod length is too short.
But if it works right,
go for a drive and make note of how often and under what circumstances, your vacuum falls below the minimum.
If your check valve is working, the booster will continue to work, even if the engine stalls, for at least one long slow braketest.
Finally, put her in park, then charge yours up to whatever maximum vacuum your engine can achieve, then shut the engine off,. Do not touch the brake pedal. The booster should maintain the vacuum above the minimum, for several minutes.
>If it doesn't, something is wrong. It could be a faulty checkvalve, a faulty control valve, or a pedal not parking properly, which could point to a too-short pushrod.
Happy Hunting.
Click to expand...
AJ/FormS said:
At what rpm does the vacuum pop up to 11/12?
My Dart booster requires about that to begin charging. It charges in a few seconds. Even on a long slow stop from whatever speed, that booster worked right down to near-stopped, at which time, it doesn't take much effort to brake as a manual.

Here's your test.
Shut off the pump.
Hook up your booster to the intake plenum; NOT an individual runner.
Make sure your vacuum checkvalve is working, get one that provides a vacuum tap on the booster side of the valve. Hook a vacuum gauge to the booster, that you can read from the cabin.
Pump your pedal a few times to empty the vacuum chamber.
Put some modest pressure on the pedal, and just maintain it, then start the engine.
When the booster comes on line, the pedal will began to fall under your foot.
Note the vacuum at which this begins.
If the pedal does not fall, rev the engine up to 10 inches vacuum, then 11 then 12 or until the pedal falls. That is your minimum vacuum for that booster.
>If the pedal does not fall, something is wrong. Either the booster is defective, or has an extremely high minimum vacuum requirement, or more likely, the pushrod length is too short.
But if it works right,
go for a drive and make note of how often and under what circumstances, your vacuum falls below the minimum.
If your check valve is working, the booster will continue to work, even if the engine stalls, for at least one long slow braketest.
Finally, put her in park, then charge yours up to whatever maximum vacuum your engine can achieve, then shut the engine off,. Do not touch the brake pedal. The booster should maintain the vacuum above the minimum, for several minutes.
>If it doesn't, something is wrong. It could be a faulty checkvalve, a faulty control valve, or a pedal not parking properly, which could point to a too-short pushrod
Happy Hunting.
Click to expand...
AJ/FormS said:
At what rpm does the vacuum pop up to 11/12?
My Dart booster requires about that to begin charging. It charges in a few seconds. Even on a long slow stop from whatever speed, that booster worked right down to near-stopped, at which time, it doesn't take much effort to brake as a manual.

Here's your test.
Shut off the pump.
Hook up your booster to the intake plenum; NOT an individual runner.
Make sure your vacuum checkvalve is working, get one that provides a vacuum tap on the booster side of the valve. Hook a vacuum gauge to the booster, that you can read from the cabin.
Pump your pedal a few times to empty the vacuum chamber.
Put some modest pressure on the pedal, and just maintain it, then start the engine.
When the booster comes on line, the pedal will began to fall under your foot.
Note the vacuum at which this begins.
If the pedal does not fall, rev the engine up to 10 inches vacuum, then 11 then 12 or until the pedal falls. That is your minimum vacuum for that booster.
>If the pedal does not fall, something is wrong. Either the booster is defective, or has an extremely high minimum vacuum requirement, or more likely, the pushrod length is too short.
But if it works right,
go for a drive and make note of how often and under what circumstances, your vacuum falls below the minimum.
If your check valve is working, the booster will continue to work, even if the engine stalls, for at least one long slow braketest.
Finally, put her in park, then charge yours up to whatever maximum vacuum your engine can achieve, then shut the engine off,. Do not touch the brake pedal. The booster should maintain the vacuum above the minimum, for several minutes.
>If it doesn't, something is wrong. It could be a faulty checkvalve, a faulty control valve, or a pedal not parking properly, which could point to a too-short pushrod.
Happy Hunting.
Click to expand...
AJ/FormS said:
At what rpm does the vacuum pop up to 11/12?
My Dart booster requires about that to begin charging. It charges in a few seconds. Even on a long slow stop from whatever speed, that booster worked right down to near-stopped, at which time, it doesn't take much effort to brake as a manual.

Here's your test.
Shut off the pump.
Hook up your booster to the intake plenum; NOT an individual runner.
Make sure your vacuum checkvalve is working, get one that provides a vacuum tap on the booster side of the valve. Hook a vacuum gauge to the booster, that you can read from the cabin.
Pump your pedal a few times to empty the vacuum chamber.
Put some modest pressure on the pedal, and just maintain it, then start the engine.
When the booster comes on line, the pedal will began to fall under your foot.
Note the vacuum at which this begins.
If the pedal does not fall, rev the engine up to 10 inches vacuum, then 11 then 12 or until the pedal falls. That is your minimum vacuum for that booster.
>If the pedal does not fall, something is wrong. Either the booster is defective, or has an extremely high minimum vacuum requirement, or more likely, the pushrod length is too short.
But if it works right,
go for a drive and make note of how often and under what circumstances, your vacuum falls below the minimum.
If your check valve is working, the booster will continue to work, even if the engine stalls, for at least one long slow braketest.
Finally, put her in park, then charge yours up to whatever maximum vacuum your engine can achieve, then shut the engine off,. Do not touch the brake pedal. The booster should maintain the vacuum above the minimum, for several minutes.
>If it doesn't, something is wrong. It could be a faulty checkvalve, a faulty control valve, or a pedal not parking properly, which could point to a too-short pushrod.
Happy Hunting.
Click to expand...
My engine makes 6 inches at idle 1000 rpm however to my surprise made 11 to 14 at 2500 rpm booster doesn’t hold vacuum so will try check valve first then booster pushrod can’t be short because I was the one to change virgin master cylinder car has 52000 miles on it penstar still on try rod ends
 
on going manual brakes: i've done three? cars over the years and just reused the power M/C no problem. and if you don't like it, go to a 15/16"
 
kursplat said:
on going manual brakes: i've done three? cars over the years and just reused the power M/C no problem. and if you don't like it, go to a 15/16"
Click to expand...
It bolts to firewall or the mount the booster is bolted to do you use same pushrod or are adaptor plates used
 
you need a manual pushrod. don't forget the rubber bushing. after the booster is removed you can gently move the MC into position and bolt it to the firewall without opening the lines. just bend to fit as needed
 
Ahoey said:
however to my surprise made 11 to 14 at 2500 rpm
Click to expand...
And the vacuum at stall is?
Once the booster is fixed, it only takes a couple of seconds to evacuate it. I mean it is a really small chamber when you think about it.
The Check valve is the key; it has to work, else the vacuum in the booster will follow the intake manifold vacuum lock-step. That would be bad. The booster has to "store" the vacuum created during high-manifold vacuum, to be used as required, including during periods of low vacuum. That's why the checkvalve is there.
The pushrod length is only right one time; when it left the factory, and IMO, it was too long right from the get-go from Chrysler. You can, over a narrow range, use the length to fine-tune the assist timing, not the amount per se, but when it starts.. If you find yourself, as is usual, diving for the windshield every time you brake, your timing is wrong for your driving style. Usually the boost is coming on too soon or rather too suddenly. Shorten the Pushrod. And vice-versa. If you find yourself pressing harder and harder in attempt to slow down,and you know the booster is charged, then lengthen the pushrod some.
There are a few caveats;
1) if the pushrod gets to be too long, the piston will cover the compensating port.If not corrected;
2)Over time your pedal will drop and mess up your boost timing, but also
3) a full pedal will not apply the brakes properly. And
4) you will eventually break the control valve, trying to put the pedal into the carburator.
so the take-away is to prove the C-port continues to work after every adjustment. One turn atta time, until you get close, then a half turn.
Happy scre, er adjusting.
 
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