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Chris_oz · 12-11-2018, 01:47 AM

I consider good vacuum anything in double numbers, this engine had 11 to 12 in Hg at idle, which is enough for brakes to work and not give drive ability issues.

Big duration and long overlap cams will kill the vacuum and other methods of boosting the brakes may be required.

12-11-2018, 01:47 AM	#944
Chris_oz Registered User Join Date: Sep 2018 Location: Newcastle, New South Wales, Australia Posts: 139	Re: Lets see pics of your truck hauling!! I consider good vacuum anything in double numbers, this engine had 11 to 12 in Hg at idle, which is enough for brakes to work and not give drive ability issues. Big duration and long overlap cams will kill the vacuum and other methods of boosting the brakes may be required.