Engine Vacuum

Reply Subscribe

Thread Tools

Search this Thread

Jun 23, 2008 | 08:37 AM

Guru_4_hire

Thread Starter

Team Owner

Joined: Apr 2002

Posts: 62,198

Likes: 1

From: All humans are vermin in the eyes of Guru VA

Cruise-In IV Veteran

Cruise-In V Veteran

Engine Vacuum

How much vacuum should I be getting with a 73 L82.

The previous owner had a single plane intake on it, that I finally got around to replacing. I remember it pulled 15-16lbs of vacuum. I put on an edelbrock EPS intake and now I am getting like 12lbs on the ported vacuum line.

I will check the manifold vacuum port when I get home from work.

Last edited by Guru_4_hire; Jun 23, 2008 at 08:50 AM.

Jun 23, 2008 | 09:16 AM

SH-60B

Melting Slicks

Joined: Mar 2008

Posts: 2,989

Likes: 198

From: Meriden CT

Manifold vac is what you want to check. 12 inches of vac might not get you power assist on the brakes. Isn't the EPS a dual plane? Is the idle the same as before?

Jun 23, 2008 | 12:12 PM

7T1vette

Team Owner

Joined: Jan 2006

Posts: 37,637

Likes: 3,114

From: Crossville TN

Changing the intake manifold only won't alter the vacuum level (unless your intake manifold gaskets aren't sealing properly). You likely have a vacuum leak somewhere.

Jun 23, 2008 | 01:31 PM

Guru_4_hire

Thread Starter

Team Owner

Joined: Apr 2002

Posts: 62,198

Likes: 1

From: All humans are vermin in the eyes of Guru VA

Cruise-In IV Veteran

Cruise-In V Veteran

What should the manifold vacuum be?

Jun 23, 2008 | 01:52 PM

lars

Tech Contributor

Joined: Aug 1999

Posts: 14,370

Likes: 6,364

From: At my Bar drinking and wrenching in Lafayette Colorado

Quote:

Originally Posted by Guru_4_hire

How much vacuum should I be getting with a 73 L82.

I am getting like 12lbs on the ported vacuum line.

Ported vacuum doesn't mean anything. You need to measure direct manifold vacuum. For info, vacuum is measured in inches of Mercury (inHg) and not in lbs.