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I am pretty sure I have a vacuum leak. At Idle I am running around 10-13 in h20 and is fairly inconsistant. I have a semi mild roller cam 228/232 dur 597/609 lift 112 lobe sep and feel my idle vacuum should be in the 14-17 range. I have checked and rechecked the carb base gasket and all lines. Carb is new. Engine has less than 3K. I have suspected it to be an issue since I firts fired it up. Next items would be power brake booster and PVC valve. How can i check the power brake booster to see if its OK. Is it as simple as pulling a vacuum on it with a mighty vac and see if it holds? Could the PVC valve be the problem? Any other areas to check.
 

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You can very carefully spray carb. cleaner near suspected vacuum leak area. If engine revs up, you found it!
 

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Use an unlit propane torch, the vacuum will suck in the gas and the RPMs will increase. Added plus to this method, no mess!

You can use a hose and a small diameter tube on the end to get pinpoint accuracy.
 

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A vacuum pump with a gauge works well. The best tool I've found is a 1/2" rubber hose. One end up to your ear of course. The things you hear and how easy it is to locate vacuum leaks will amaze you.
I think that your cam has a little to do with it. That's not a mild street cam for sure. Keep in mind that your initial timing also has something to do with the vacuum.
Good luck,
David
 

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With your cam, 10~13 in/merc isn't out of the question.

I'd check it anyway, just to be sure.
 
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