Video STS TT
Drifting
Joined: Sep 2005
Posts: 1,788
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From: Tallahassee FL
Yeah, sounds reasonable enough. I have a boost gauge on a pillar mount and it still puzzles me that I see NO boost at all during regular driving. The turbos certainly should be spinning even at 2K rpm, so why isn't there at least a pound or two of boost registering? Wouldn't ANY boost give a "boost" over NOT being boosted?
Thread Starter
Race Director
Joined: Apr 2005
Posts: 11,556
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From: SoCal Twin Turbo, Any Questions?
St. Jude Donor '06-'07
Originally Posted by Rich Z
Yeah, sounds reasonable enough. I have a boost gauge on a pillar mount and it still puzzles me that I see NO boost at all during regular driving. The turbos certainly should be spinning even at 2K rpm, so why isn't there at least a pound or two of boost registering? Wouldn't ANY boost give a "boost" over NOT being boosted?
-2 lbs (naturally aspirated engine) + 2 Lbs (from turbos at low RPM) = O MAP (manifold absoulte pressuer) so if you have a boost gague that reads into vacume you will see this otherwise the gague will just sit on zero till you make positive boost at around 3 grand
Racer
Joined: Feb 2006
Posts: 367
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From: Harrisburg PA
My car runs 19psi of vacuum at idle and a little less cruising...lag is swinging it over to full boost...get a boost/vacuum gage...then you can see whats going on...and see if there are any vacuum issues
Thread Starter
Race Director
Joined: Apr 2005
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From: SoCal Twin Turbo, Any Questions?
St. Jude Donor '06-'07
Originally Posted by C5A4TT
My car runs 19psi of vacuum at idle and a little less cruising...lag is swinging it over to full boost...get a boost/vacuum gage...then you can see whats going on...and see if there are any vacuum issues
Drifting
Joined: Sep 2005
Posts: 1,788
Likes: 2
From: Tallahassee FL
Yeah, this sounds logical. Got a gauge installed but it is BOOST only and registers from 0 to 35 lbs. So it basically never moves during normal driving. Maybe I should replace it with a Vacuum/Boost gauge so it would mean more to me. Had it installed by AntiVenom, so I guess I need to figure out what type of gauge I need. There is a bewildering array of them when I look through the catalogs. 
I'm guessing it is a 2 1/16 inch one with a mechanical hookup rather than electrical. Maybe I need to talk to Greg and make sure, though. I guess it just pops out of the holder and the connections are a simple swap over.
One noteworthy observation is that my average gas mileage dropped from 32 mpg to 28 on the highway coming home with it. What sort of results have others gotten in this department?
Oh, one other thing.... How would I know if there are any "vacuum issues" since I really don't know what is "normal"?
I'm guessing it is a 2 1/16 inch one with a mechanical hookup rather than electrical. Maybe I need to talk to Greg and make sure, though. I guess it just pops out of the holder and the connections are a simple swap over. One noteworthy observation is that my average gas mileage dropped from 32 mpg to 28 on the highway coming home with it. What sort of results have others gotten in this department?
Oh, one other thing.... How would I know if there are any "vacuum issues" since I really don't know what is "normal"?
Thread Starter
Race Director
Joined: Apr 2005
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From: SoCal Twin Turbo, Any Questions?
St. Jude Donor '06-'07
my gas milage improved in highway
went down considerably for around town and city driving, but that has to to soley with my right foot
went down considerably for around town and city driving, but that has to to soley with my right foot
Drifting
Joined: Sep 2005
Posts: 1,788
Likes: 2
From: Tallahassee FL
Originally Posted by NAVY08
my gas milage improved in highway
went down considerably for around town and city driving, but that has to to soley with my right foot
went down considerably for around town and city driving, but that has to to soley with my right foot
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Racer
Joined: Feb 2006
Posts: 367
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From: Harrisburg PA
Originally Posted by NigelTufnel
My highway gas mileage remained approximately the same (about 30-31 with the cruise set at about 70, give or take).
Dont tell anyone...but I run a mechanical Sunpro boost/vacuum gage for $20 from PepBoys.
Le Mans Master
Joined: Jan 1999
Posts: 5,135
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From: Long Island NY
Originally Posted by C5A4TT
Dont tell anyone...but I run a mechanical Sunpro boost/vacuum gage for $20 from PepBoys.
Drifting
Joined: Sep 2005
Posts: 1,788
Likes: 2
From: Tallahassee FL
Originally Posted by Hammer
My boost gauge has a digital read out, I don't like it. Having it changed over the winter.
But one thing I am changing is to take out the boost only guage and put in a vacuum/boost one. I think that would be a better indicator to have....
Drifting
Joined: Sep 2005
Posts: 1,788
Likes: 2
From: Tallahassee FL
Originally Posted by Pumba
Rich,
When you buy the new vacuum - boost gauge spend the extra money and get a liquid filled gauge. They last much longer and give a more stabil reading.
Too late, I just ordered one last night. It's the Z series model of Autometer. I wanted it to match the fuel pressure gauge also on the pod.....
But when it comes time to replace them, I'l keep this in mind.
Thanks.