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Guys I need a vacuum pump for my s10 because I just dont have enough vacuum for the booster even with a vacuum can. My 350 has a cam that really does not produce any vaccum. I have tried my own way thus far I went to the salvage yard and got a vacuum pump out of a caddy and hooked it up put it only can produce about 8inchs and I really think I need about 12 as a min just to make the booster to work. Oh and on its own the motor is only produceing about 10 inches at normal rpms and of course I can get about 20 in the can if I rev to 5000 rpms but cant do that everytime I need to use the brakes. I have priced aftermarket pumps for what I need and there very costly. Here is my question? An air compresser and a vacuum pump do the same thing dont they? They both pull air and one stores it and the other just releases it. My thought is taking a 12v air compresser and pluming the peice that sucks air into the vacuum can. Make sense to anyone. will it work or has anyone tried before?


justspeed
 

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You need to either buy an electric vacuum pump capable of sustaining 18" of vacuum (Master Power Brakes) or delete the booster and go to manual brakes.
 

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Try this...

Doc here :pimp:

Try this, Get a Vacuum Check valve and install it on the canister Vacuum input line.

This will not allow canister pressure to rise and fall with induction changes...It will only allow vacuum one way, into the canister.

This way the canister will act as a "buffer", as it should between the intake and the accessory item.

Check your Canister, and system for leaks...Be Sure it's all tight otherwise you'll be defeating your purpose.

Just put a Hand Vacuum pump to the Canister in line and pump it down to 20 in hg...with the rest of the system in tact, It should hold , not drop less than 2 in hg in 15 minutes. If so, find and fix the leaks.

Hope it helps!

Doc
 

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vacuum vs. compressor

Hi, I am no expert on the subject but, I believe that compressors and vacuum pumps are designed to do just how they are named. My feeling is that if you put a "load" on the intake side of a compressor, you will not get anything equal to the amount of air being pushed out of the other side, just because of its design. There is no harm in trying though, it may just pull enough for you. Most compressors I believe, have no way to hook a fitting to the intake side. Usually there is just an opening that houses a filter. How would you hook up to it? Also, my Vette only pulls about 10" of vacuum and I have no trouble with the brakes. Just a couple of thoughts. Keep us posted.
Dennis
 

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Discussion Starter #5
oh the vacuum can has a check valve built in. Its a can I bought from crane and I know it has the check valve because I remember reading about it in the instructions that came with the can.



Power brakes working good on only 10in vacuum? hmmmmmm

Makes me think! I had an 83 camaro that I built a nice small block for and the power brakes never worked good until I got the vacuum up to 14in and I did that by moving to a smaller cam because as many of us know a third gen f-body is not a good wet weather or hard breaking car so rather than finding myself wraped around a tree I settled for less power but this time around I will not settle. I am very much enjoying the 330hp in my s10.

justspeed
 

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10 in. vacuum

I have no answer but, brakes are fine. Last two cams I had produced about the same vacuum and all has been well. This time, we also installed a super charger, and still no problem, Just lucky I guess.
Dennis
 

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FORD has two HYDRO-BOOST systems that are fairly easy to retro-fit. Doesn't CHEV?

Running a car with an inoperative power booster is just asking for it. Manual disc brakes are not that much harder to apply.
 

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GM cars have pumps due to the motors not making enough vacuum from the factory. They are located under the driver's side fenderwell.
Buick
82 Skyhawk-J
82- 85 Skylark-X

Cadillac
82 Cimmaron
Chevrolet
84-86 Celebrity-A
82 Caprice-B
82 Cavalier-J
82-85 Citation-X

Oldsmobile
86 Cierra-A
82 Firenza-J
82-84 Omega-X
Pontiac
85-86 6000
82 J2000
82-84 Phoenix-X

Or GM part number 22034995
 

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Discussion Starter #9
great info but how much does the pump in any one of these cars pull?
 

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Maybe this has already been said, but why not convert to manual brakes? Then you have more room under the hood, and everything is that much simpler. You should have plenty of stopping power in a light vehicle like an S10. Crap, my F100 has manual brakes, and I tow a 3000 lb boat with it, no problem.
 
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