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stempak
09-21-2007, 01:44 AM
I replaced my headgaskets and rebuilt my heads. my boost gauge before replacment never went below zero boost. Now it goes to around neg. 23in? It seems to run fine with maybe a little hesitation? I would like to have it the way it was though not going negitive.

THE BIRDMAN
09-21-2007, 02:01 AM
You're boost gauge should go to negative.Because you're not always "in boost" the neg side you are talking about is showing your engine vacuum.So 23in is 23 inches of vacuum which is a good reading indicating you don't have a vacuum leak.So before you must of had a leak somewhere that was keeping the gauge from going into negative but you must have corrected the issue while you had it apart.

Jay

None2Slow
09-21-2007, 02:16 AM
So the gauge going negative IS a good thing and is perfectly normal.

THE BIRDMAN
09-21-2007, 02:57 AM
So the gauge going negative IS a good thing and is perfectly normal.


Yes that is how it's suppose to operate.Like when you first start the car and let it idle you should see it in the neg/vaccuum side.When you're at cruise it'll also be on the vac side then the more you push the pedal you'll see it come up to zero then go on the boost side of the gauge.

Jay

Want2LearnTBIRD
09-21-2007, 10:01 AM
this guy makes me look smart :D:D:D

rickbtbird
09-21-2007, 11:16 AM
this guy makes me look smart :D:D:D

We'll have to see about that. ;)

None2Slow
09-21-2007, 08:20 PM
Yes that is how it's suppose to operate. Like when you first start the car and let it idle you should see it in the neg/vaccuum side.When you're at cruise it'll also be on the vac side then the more you push the pedal you'll see it come up to zero then go on the boost side of the gauge.

Jay



Heh, yes I know its normal, thats what I was getting at. All engines at idle create vacuum and unless the gauge is set for vacuum you wont "see" it. If you run just a boost gauge, then obviously you wont see vacuum. So, I guess if you don't want to see it go negative, buy an after market boost gauge.