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Discussion Boards => Aero Cars => Topic started by: taxspeaker on October 30, 2018, 07:58:46 PM

Title: Vacuum & cams
Post by: taxspeaker on October 30, 2018, 07:58:46 PM
On our bluebird that we bought from the hippie drag racer we have an issue with both the headlights and the power brakes. rakes are mushy, even after we did a complete brake job, bled all carefully and adjusted, and headlight doors don't close, but lines appear fine. The engine has some kind of cam that was added that has a small "lope" and what little is left of my memory tells me that the lift or duration or something like that ruins the vacuum generation, which would affect both of the above issues.

Is there a measurement or reading that can tell me if the engine generates enough vacuum to cure these issues?
Thanks

BTW get ready for an anthracite gray (gloss) color picture on this bird by Christmas as we are working on it now.
Bob
Title: Re: Vacuum & cams
Post by: odcics2 on October 30, 2018, 08:01:45 PM
What's your vacuum at idle?
Title: Re: Vacuum & cams
Post by: hemi-hampton on October 30, 2018, 08:07:05 PM
Yes, there is a Vacuum gauge to measure Vacuum. I had the same problem with my Car with big cam. Forgot what the Vacuum # should read but somewhere around 16 if I remember right. LEON.
Title: Re: Vacuum & cams
Post by: taxspeaker on October 30, 2018, 08:36:08 PM
Thanks, I get home tomorrow night and will stick a gauge on it and see
Title: Re: Vacuum & cams
Post by: DAY CLONA on October 30, 2018, 09:23:42 PM
If the car is a 4spd, 10 inches of vac reading is about the minimum at idle, for a power brake vehicle, an automatic will require 12 inches minimum at idle to have a successful recovery of vacuum to safety perform repeated braking, the manual tranny vehicle recovers faster due to clutching the engine for braking, if the vehicle has a dual diaphram brake booster you'll need at least a minimum of 12-14 inches at idle for safe repetitive braking with an automatic.... your light pod issue sounds like switch/vac resv canister related? or perhaps deteriorated vacuum lines also?  if the cam is robbing you of vacuum due to it's overlap profile, your only choice is cam change or vacuum pump assist...
Title: Re: Vacuum & cams
Post by: hemi68charger on October 31, 2018, 08:01:19 AM
Bob..

I would also get a simple hand vacuum pump from your local auto parts store and manually try to close your headlamp buckets? It is easy to just disconnect the connect up front ( there should be a connector near the vicinity of the nose. Close the doors and just hold it there and see if they start to open again caused by the safety springs ( if they are still on the car ). This way you have isolated the vacuum system from the headlamp bucket pods....... Then work yourself backwards.... Also, isolate the vacuum can under the battery to see if it still holds vacuum by the same principle using the hand vacuum pump....

Troy
Title: Re: Vacuum & cams
Post by: Moparpoolman on November 01, 2018, 04:32:24 PM
I would check the power booster, maybe when checking the vacuum with a gauge disconnect the booster and plug the line just to make sure you're not losing vacuum from the booster
Title: Re: Vacuum & cams
Post by: taxspeaker on November 03, 2018, 06:25:11 PM
Thanks for the leads. Pulling only 6" at idle-pretty strong cam (unknown numbers-before my ownership). Guess the next step is an electric vacuum pump. Anyone have one of them installed?
Title: Re: Vacuum & cams
Post by: taxspeaker on November 03, 2018, 06:46:55 PM
I have listed car for sale in Craigslist Louisville by the way.
Title: Re: Vacuum & cams
Post by: 303 Mopar on November 05, 2018, 01:17:54 PM
Quote from: taxspeaker on November 03, 2018, 06:25:11 PM
Thanks for the leads. Pulling only 6" at idle-pretty strong cam (unknown numbers-before my ownership). Guess the next step is an electric vacuum pump. Anyone have one of them installed?

I installed one in the trunk of my '71 Challenger. It was loud an obnoxious despite the rubber mounts.  This would be my last choice.
Title: Re: Vacuum & cams
Post by: odcics2 on November 12, 2018, 03:42:25 PM
Maybe a smaller cam would help sell it?   :Twocents: