Low vacuum

[Jetblack]

My vacuum at idle is only around -12 Hg but I hear others are at -22Hg. I have FP2's and 6-bolt. What is normal and what can be causing this, leak maybe?

 

[SoonToBeDSM06]

Yea there are a few places to check for leaks like that. I had a few and only had 15 vac at idle but since i fixed them i have 21 vac. Make a leak tester real quick and place it on the TB Elbow if your only into finding those vac leaks. Places like the TB shaft seals, TB Gaskets (inner and outer), Injector insulators, and vac hoses and brake booster hose, and the BISS o-ring. I replaced my injector insulators because they were hard plastic and old and new rubber ones made it seal good. Try those places

 

[danamo250]

Are you at sea level or close to. Remember higher elevations will reduce vacuum.

 

[zachdeagle16]

6BOLTS ARE ONLY SUPPOSED TO VACCUME AT ARROUND 15Hg AND 7 BOLTS ARE SUPPOSED TO VACCUME AROUND 20Hg THEY ARE DIFERENT BECAUSE OF THE COMPRESSION RATIOS OF THE PISTONS.

 

[1fast97gsx]

12 sounds right with cams. I was pulling around 12-13 at 1000 rpm with 272s on a 9:1 motor.

 

[92GSXBaltimore]

my 6 bolt pulls about 22hg

..and i have a massive valve cover leak