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Old Jul 26, 2018 | 10:17 PM
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can someone recommend a vacuum pump, I have very little brakes. Thanks
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Old Jul 27, 2018 | 07:12 AM
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Originally Posted by johnnied
can someone recommend a vacuum pump, I have very little brakes. Thanks
I just installed this on my 1978 last week:

https://www.summitracing.com/parts/sum-760152
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Old Jul 27, 2018 | 07:43 AM
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Are you referring to the fact that you have a cam with long duration, low vacuum, so the power brake booster is not assisting?
Or
Are you referring to the brake pedal is soft, often going to the floor in which case a vac pump is of no help.
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Old Jul 27, 2018 | 08:32 AM
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Originally Posted by HeadsU.P.
Are you referring to the fact that you have a cam with long duration, low vacuum, so the power brake booster is not assisting?
Or
Are you referring to the brake pedal is soft, often going to the floor in which case a vac pump is of no help.
It's because of the cam
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Old Jul 27, 2018 | 09:14 AM
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I only have 11-13 inches of Vac myself, but still have a working booster. Do you suppose you have some leaks somewhere?
Could be the booster itself or the check valve / filter line to the booster.
As you know, the trouble with C3s is there is so much relying Vac to operate. I guess the solution sometimes is a pump.
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Old Jul 27, 2018 | 11:09 AM
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Originally Posted by HeadsU.P.
I only have 11-13 inches of Vac myself, but still have a working booster. Do you suppose you have some leaks somewhere?
Could be the booster itself or the check valve / filter line to the booster.
As you know, the trouble with C3s is there is so much relying Vac to operate. I guess the solution sometimes is a pump.
The problem only started after cam change. Do you run the pump straight to the brake booster? or to a reserve canister and then to the booster?

Last edited by johnnied; Jul 27, 2018 at 11:14 AM.
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Old Jul 27, 2018 | 12:53 PM
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Originally Posted by johnnied
The problem only started after cam change. Do you run the pump straight to the brake booster? or to a reserve canister and then to the booster?
My engine has a huge cam, and only has 6 inches hg at idle.. so, ZERO boost for brakes .. Elect Vac Pump solves that. I bought mine from SSBC about 9 years ago.. works great.. holds constant 18-20 inches hg .. I mounted mine where the charcoal canister used to be, right under the booster, connect it directly to the booster .and 12v keyed power .. you will have excellent brakes if everything else is up to par.. only runs when needed
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Old Jul 27, 2018 | 01:40 PM
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Are you guys just running this for the brake booster or are you connecting it to the headlight (and wiper door in my case) system too?
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Old Jul 27, 2018 | 02:39 PM
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Originally Posted by theandies
Are you guys just running this for the brake booster or are you connecting it to the headlight (and wiper door in my case) system too?
My headlights seem to work fine I just need it for brakes
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Old Jul 27, 2018 | 02:43 PM
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my 81 has direct connection to the manifold just behind the carb, the vacuum line should be dedicated to the booster from the source, suppose your opening the headlights and a deer jumps out, for those 5 seconds of the doors opening you wont have any brake assist.
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Old Jul 27, 2018 | 03:02 PM
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Originally Posted by johnnied
My headlights seem to work fine I just need it for brakes
Just wondering if anyone is running one that way. I always thought of going over to a dedicated vacuum pump because that is what they run of small aircraft engines (engine driven though, not electric). Being an aircraft mechanic for years I'm just thinking out loud I guess since my vacuum system works ok and I don't have power brakes.
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Old Jul 27, 2018 | 03:56 PM
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Originally Posted by theandies
Are you guys just running this for the brake booster or are you connecting it to the headlight (and wiper door in my case) system too?
Strictly brake booster for me
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Old Jul 27, 2018 | 04:04 PM
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check out Leed brakes.com they have a nice pump. 716-852-2139
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