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Wild Cam " Not Enough Vacuum For Power Brakes"

Old 01-14-2002, 05:24 PM
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73-454
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Default Wild Cam " Not Enough Vacuum For Power Brakes"


Any Suggestions on How I can Get more Vacuum in my Power Booster Not enough to work my brakes properly
Old 01-14-2002, 05:31 PM
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MasterDave
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Default Re: Wild Cam " Not Enough Vacuum For Power Brakes" (73-454)

Summit and the such have reservoir canisters to assist in this problem. Look in the cam section. Prices run from $34 to $80. :cheers:
Old 01-14-2002, 05:32 PM
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mountainmotor
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Default Re: Wild Cam " Not Enough Vacuum For Power Brakes" (73-454)

I would suggest a vacuum canister from Jegs High Performance.Big cams = :cool:
Old 01-14-2002, 05:32 PM
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The Dude
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Default Re: Wild Cam " Not Enough Vacuum For Power Brakes" (73-454)

Vacuum reservior as an add-on, maybe?

What cam do you have? Mine's a 244/252 duration @ .050" lift solid cam and, from what I can tell, my power brakes, transmission modulator, headlights, PCV and other vacuum accessories work just fine--even with that lopey thing in there. (And with a slightly less-than-airtight booster.)
Old 01-14-2002, 05:53 PM
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73-454
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Default Re: Wild Cam " Not Enough Vacuum For Power Brakes" (The Dude)

The previous owner installed a com cam Part # 11-213-3, grind # CB 292h-10
Gross Valve Lift .55 intake and exhaust
Duration of 292
The above stuff means nothing to me. I understand that it is a very Lumby cam, The 454 dosn't idle very well. The power brakes work fine if I put the tranny in 'N" before I APPLY THE BRAKES

Old 01-14-2002, 06:11 PM
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James
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Default Re: Wild Cam " Not Enough Vacuum For Power Brakes" (73-454)

Master Power Brakes also sells a electric vacum pump that will fix this problem.
They are little expensive though.
Old 01-14-2002, 08:26 PM
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Default Re: Wild Cam " Not Enough Vacuum For Power Brakes" (James)

I have a Summit vacuum canister, fits exactly (with a little inginuity) where you carbon canister is located. That really helped my vacuum assist brakes, worth the $40
Old 01-14-2002, 08:37 PM
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1979toy
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Default Re: Wild Cam " Not Enough Vacuum For Power Brakes" (73-454)

The power brakes work fine if I put the tranny in 'N" before I APPLY THE BRAKES
Sounds like your engine could use a high stall torque convertor.
Old 01-14-2002, 09:38 PM
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dlw
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Default Re: Wild Cam " Not Enough Vacuum For Power Brakes" (73-454)

I have a 292 duration cam in mine and my brakes are fine. A few weeks ago a deer stepped out in front of me and I tested them well. I do need a stall torque converter but thats next project.
Old 01-14-2002, 10:31 PM
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73-454
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Default Re: Wild Cam " Not Enough Vacuum For Power Brakes" (dlw)

Thank-you for your suggestions, I will ckeck-out the canasters, I just hope they are not very large I hate a lot of stuff in the engine area, I went through a lot of trouble and cost to convert to flex a lite fands in the hopess of clening up the engine. Thanks again
Old 01-14-2002, 10:37 PM
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MIKER
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Default Re: Wild Cam " Not Enough Vacuum For Power Brakes" (73-454)

The camshaft may not be the only contributor to this vacuum problem.
Could proper adjustment of the carbureator improve vacuum?
Could there be a vacuum leak?

Just consider all of the possibilities before spending money.
Old 01-15-2002, 08:55 AM
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Robert8096
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Default Re: Wild Cam " Not Enough Vacuum For Power Brakes" (73-454)

Try this. It is a kinda expensive :cool: :jester
http://www.mpbrakes.com/mp27sr.htm
Old 01-15-2002, 10:45 AM
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Monkeywrench
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Default Re: Wild Cam " Not Enough Vacuum For Power Brakes" (73-454)

I have the same problem. When I'm running in 4th and hit the brakes, no power assist. If I shift it into neutral and then apply brakes no problem. Same wild cam on mine too.

Wasn't there a thread a while back about a hydraulic assist that replaced your booster. I think it was used in the BBs where you couldn't get to the valve covers easily...Anyone remember this?
Old 01-15-2002, 12:17 PM
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Default Re: Wild Cam " Not Enough Vacuum For Power Brakes" (Monkeywrench)

I have also heard that some guys have installed an electric fuel pump for their fuel and are using the mechanical pump for the power brake booster. Has any-one tried this.
Old 01-15-2002, 07:58 PM
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ZD75blue
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Default Re: Wild Cam " Not Enough Vacuum For Power Brakes" (73-454)

about the hydrolic assist... Norval up in canada has one of these on his 75... out of a mid 80's ( i think mid 80's) truck, that is crank powered instead of vaccum... he could tell you more than i about it tho... i think the weight savings would be good too
Old 01-15-2002, 08:21 PM
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The Dude
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Default Re: Wild Cam " Not Enough Vacuum For Power Brakes" (73-454)

Ah, you have a big block(?) The cam specs I listed above are in a small block car.
Old 01-15-2002, 10:58 PM
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Default Re: Wild Cam " Not Enough Vacuum For Power Brakes" (73-454)

another option is to use the power steering pump/brake assist used on the early gm diesels - should bolt right on - dave

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Old 01-16-2002, 05:09 AM
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Default Re: Wild Cam " Not Enough Vacuum For Power Brakes" (73-454)

73-454,
You might want to look into other vacumm leaks.Many can be found under the hood on a Corvette.
Also if you are using a stock Quadrajet the motor will not idle well period same with a Holley that that is out of tune and has a blown power valve..Unless the motor has been built with say 8.1 compression for an example the wild idle you describe can and should be just a good lope.That cam will idle pretty good in a 10.1 468 with a single 4150 Holley @ 850-900 rpm with a dialed in Holley.Now performance with your gears and automatic might be a different story.You will still need a canister in my opinion.


[Modified by mountainmotor, 3:18 AM 1/16/2002]
Old 01-16-2002, 08:53 AM
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norvalwilhelm
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Default Re: Wild Cam " Not Enough Vacuum For Power Brakes" (ZD75blue)

I have a hydraboost used in diesel trucks and vans. They don't have any vacuum and use the power steering pump for steering and braking. The unit is extremely powerful and doesn't care what vacuum you have. It is also very compact, like running 2 master cylinders. Leaves lots of clearance for tall valve covers. My last unit is from a 94 one ton dually. Cost $50 at the wreckers complete in perfect shape. My brake are among the most powerful on the forum. I can effortlessly lock all 4 wheels at 50 mph. Not necessarily a good thing but they sure work, gives you a good feeling knowing they are that powerful.
Old 01-16-2002, 09:08 AM
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BLT-71
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Default Re: Wild Cam " Not Enough Vacuum For Power Brakes" (norvalwilhelm)

My 85 Caprice Wagon uses the same system. Power steering boosts the power brakes via fluid. Works great and compact. I remember how little space was in my brothers 454 vette and this would have been nice.

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