Wiring Diagram Vacuum Gauge Vw Bug

Author Message sammywells
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Posted: Tue Jun 06, 2017 7:36 pm   Post subject: Re: vacuum gauge
Most vac gauge instructions list 14 to 22 hg. But no set in stone answer, condition of the engine, compression, cam, timing, there is a lot that effects the vacuum reading. Altitude will reduce the vacuum reading. Now with that said I like to see around 18 hg steady, a blip of the accelerator should tank that reading then it should pop up to around 22, then settle back to the initial reading. Then again I have had a bus engine that was rock solid at 15 hg ran perfect. The key is a steady reading, not a lot of fluctuation. Take timing with a vac gauge carefully for it is real easy to get too lean which will cook an air cooled engine.

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Posted: Wed Jun 07, 2017 1:12 am   Post subject: Re: vacuum gauge
The factory DVDA and SVA distributors can mess with the air flow so much that any muscle car enthusiast will say you have a burned valve or ring issues. Nonsense; post your carb and distributor setup first and vacuum test results after. Robbie _________________ www.airschooled.com

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Posted: Wed Jun 07, 2017 4:39 pm   Post subject: Re: vacuum gauge
Vacuum at 15 is slightly low, but many variables here to contend with. Here is a decent chart with info for air cooled VW engines. These engine have a unique vacuum signature, unlike many other engines. If you do measure the vacuum, and have dual carbs, you need to be able to connect the two sides of the engine to read the vacuum correctly regarding this information. Reading only one side of the engine kills this chart, plus it is really hard to do (needle bounces all over the place). Hope this helps you out! _________________ Jimbo There is never enough time to do it right the first time, but all the time necessary the second time! nshaddox wrote: Plus I tend to prefer these impossible projects that take way too much time. There�s no thrill in easy projects. Challenges are fun. 67rustavenger wrote: GFY's Xevin and VW_Jimbo!

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Posted: Thu Jun 08, 2017 5:26 pm   Post subject: Re: vacuum gauge
Yes, they should taper out to the normal range. When the engine and all of its systems are in scynch with one another, you get that "good" vacuum area on the chart. Any other reading and something is off! Glad the chart helped! Sometimes it is nice to be able to see it! _________________ Jimbo There is never enough time to do it right the first time, but all the time necessary the second time! nshaddox wrote: Plus I tend to prefer these impossible projects that take way too much time. There�s no thrill in easy projects. Challenges are fun. 67rustavenger wrote: GFY's Xevin and VW_Jimbo!

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