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The bigger cam seems to be causing my power brakes not to work slowing down at redlights and such.
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was gonna post a video of my car running but I cant figure out how to post it....Steve says it is 6sally6 approved.
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If you already have your video in YouTube, You can easily attach a YouTube video link using the "Full" post window instead of using the Quick Post window.
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If you use a vacuum can remember that you need a check valve so vacuum only goes into the can from the engine. Without the valve the can will empty when the engine vacuum goes to zero.
As far as a pump goes, my Diesel has one, as lacking a throttle plate Diesels do not make any vacuum. You would never know its there. Its a small pump and a plastic tank atop the RH inner fender. It does not run the brakes on that truck though (uses hydroboost). I've never seen or heard of one going bad, so I would bet the tank and pump are a dime a dozen in salvage yards. I think any Super Duty from '99-'07, and I assume even down to the present day, has these parts.
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BILLY WALTON from GEORGIA wrote:
The bigger cam seems to be causing my power brakes not to work slowing down at redlights and such.
Hi BILLY, I put a vacuum can in my 66 in 04 for the same reason. I got it from Summit for about $50. It came with the check valve mentioned by TKO and has worked great.
Hope this helps. Part # CRN-99590-1
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Thinking of free things to check besides ensuring that your booster's check valve is good and making sure the booster itself isn't leaking as well as the vacuum hose going to the booster. I remember back in the day doing things like adjusting the carb mixture screws to get highest vacuum and increasing timing, but that will affect the rest of the curve so careful on that one. Lastly I'd check your idle speed as well, sometimes folks want it real low to get the chop chop and that doesn't help with idle vacuum
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Raymond_B wrote:
"I'd check your idle speed as well, sometimes folks want it real low to get the chop chop...
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People REALLY do that ?! (how juvenile !!)
6sally6
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BILLY.......why not try tuning the timing and carb and see IF ya can get it work'in better !?! Unless it's REAL snotty idling ...I don't know..
6sally6
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Raymond_B wrote:
Thinking of free things to check besides ensuring that your booster's check valve is good and making sure the booster itself isn't leaking as well as the vacuum hose going to the booster. I remember back in the day doing things like adjusting the carb mixture screws to get highest vacuum and increasing timing, but that will affect the rest of the curve so careful on that one. Lastly I'd check your idle speed as well, sometimes folks want it real low to get the chop chop and that doesn't help with idle vacuum
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my buddy does have it idled low...I will idle it up a little
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Bullet has an electric vacuum pump on his 66
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6sally6 wrote:
Raymond_B wrote:
"I'd check your idle speed as well, sometimes folks want it real low to get the chop chop...
"
People REALLY do that ?! (how juvenile !!)![]()
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6sally6
No judgement here! Just something to look at.
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MS wrote:
Bullet has an electric vacuum pump on his 66
Close. Bullet had a mechanical pump which he removed when he went back to a stock cam. He sent me his old pump a couple of weeks ago.
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Billy; Best brake pressure I could get with no pump and the cam I was running was 650 - 700 lbs at the caliper....not nearly enough. I put on a custom bracket with a mechanical vac pump from a E450 diesel and a vac tank with check valve. The pump held 17" of vac and I was then able to measur 1200 -1400 lbs of brake pressure. Problem solved.
For you, unless you want to fab up a bracket, I would do as TKO suggests and find a boneyard electric vac pump and connect it through a check valve to a tank. That should solve you problem.
BB1
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On a current project - a turbo SBF in a 46 Ford - I picked up two Volvo turbo car pumps/check valves/sensor-switches. There are a number of how-to's you can find with searches on how to plumb these in. The pump only operates when vacuum is low on the brake booster side. Under turbo boost the check valve prevents pressure from entering the brake booster but if there is sufficient vacuum already the pump won't run. In a N/A application, it will simply sense vacuum on the booster side and if it dips, the pump will activate. I'm going to trigger a relay with the Holley EFI so that the pump will only run when the engine is running. If this wasn't an underfloor brake setup I would have installed a Hydroboost.
Here's a pretty good overview - =13px
On my 66 I installed a Hydroboost as part of the build since I knew I would have low vacuum and I needed the space. I always have good brake pressure regardless of what the engine is doing.
But, I'd use a vacuum gauge first and see if a combination of idle speed, idle mixture, and timing can improve your idle vacuum.
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BILLY....just for S & G's... post the Lift, Duration@050, and LSA of the cam you installed.
It might help us 'give-you-a-fix' for your vacuum issues.
Also, it might help others when choosing a camshaft with power brakes and/or A/T.
(make this a learning opportunity...sorta-kinda)
6sally6
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6sally6 wrote:
BILLY....just for S & G's... post the Lift, Duration@050, and LSA of the cam you installed.
It might help us 'give-you-a-fix' for your vacuum issues.
Also, it might help others when choosing a camshaft with power brakes and/or A/T.
(make this a learning opportunity...sorta-kinda)
6sally6
Howards Roller part number 221275-12
Lift: .528 / .533, Duration @ .050: 217 / 225, Centerline: 108
Camshaft Type: Hydraulic RollerBasic RPM Range: 1200 to 5600
Valve Lift Intake: .528
Valve Lift Exhaust: .533
Duration Intake: 270
Duration Exhaust: 278Duration at 050 Intake: 217Duration at 050 Exhaust: 225
Lobe Separation: 112Intake Centerline: 108
Last edited by BILLY WALTON from GEORGIA (3/10/2025 7:38 PM)
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Yeah, with an LSA that tight on that profile I'm betting ti just doesn't produce enough vacuum. If it was 112 or 114 maybe, but I would think there's just too much overlap to produce good idle vacuum.
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I am not good at any of these mods I wish someone lived close enough to check it out
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I have a Leeds electric brake pump on my 65 for that very reason and always have thru the dash good brakes now.
I have 107 LSA on my 289
Last edited by Cab4word67 (Yesterday 10:26 AM)
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Cab4word67 wrote:
I have a Leeds electric brake pump on my 65 for that very reason and always have thru the dash good brakes now.
I have 107 LSA on my 289
Where did you install the pump and does it make a lot of noise?
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BobC wrote:
Hi BILLY, I put a vacuum can in my 66 in 04 for the same reason. I got it from Summit for about $50. It came with the check valve mentioned by TKO and has worked great. Hope this helps. Part # CRN-99590-1
How many friggin' Bobs are there on this site? Dayum.
Billy - Summit is out of stock on the one Bob#22 mentioned, but Jegs has theirs in stock ready to ship and it's $40. Plug and play, drop dead easy install. Part Number: 555-63010
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TKOPerformance wrote:
Yeah, with an LSA that tight on that profile I'm betting ti just doesn't produce enough vacuum. If it was 112 or 114 maybe, but I would think there's just too much overlap to produce good idle vacuum.
ACTUALLY...(Ya I get to do an 'actually'..) the LSA on BILLY's camshaft IS 112*.
It looks like it has 4* ground into it. Equaling 112* Lobe CENTERLINE.
THEREFORE.. ACTUALLY (WOW!)...it looks to me like a good tune-up on the timing curve and carb would give enough vacuum to run the brakes... (a vacuum leak could be a possibility also)
That 225* of exhaust timing is pretty massive when paired with the 217* intake !
(I bet it REALLY has a Thump! in that idle !)
Those figgerz are more appropriate when running nitrous!
Since BILLY ain't 'all-that-and-a-bag-of-chips' when it comes to tuning on his engines
(I don't mean that in an ugly way BILLY....butt-we go back a ways so I hope you unnerstand)
It might be simpler to just go with the vacuum can.
You 'COULD' retard the cam timing 4* or so and shorten the exhaust timing to 221* BUTT that would change the intake timing the same amount and might make it "soggy"(instead of snotty!)
I'd buy the can.....plumb it in !
6sally6
PS Soooo maybe this does away with my ACTUALLY&THEREFORE...I don't know
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