boost gauge Q's

[venom2097]

Can anyone explain why the gauge works only under load? What I mean is if I'm sitting still and rev to to 6k rpm the gauge reads 0, but if I'm moving it reads 15 or whatever.

PS: anyone know how high altitude affects the amount of boost I can use?

 

[IPT]

What brand of boost gauge do you have. I have the auto meter phantom and is reads VACUUM and boost. IF you only have the boost side you will only see it move when you are under boost.

 

[Blixx]

If you mean, why doesn't it show boost while revving when stopped, that's because your engine isn't building any boost. There isn't enough pressure without load to build boost with the turbo.

Blake

 

[venom2097]

Originally posted by Blixx
If you mean, why doesn't it show boost while revving when stopped, that's because your engine isn't building any boost. There isn't enough pressure without load to build boost with the turbo.

Blake

That kinda answers my Q, but if I'm not building any boost where is it all going? I rev the motor from under the hood and I can hear/feel the BOV open, but I never see the WG open(unless it's already open?) so wheres the boost going?

 

[Bohrn]

as you know when you hit the gas it takes a second or so to build the boost. if you could make the engine rev long enough you might see boost, but as the other person said, you need load to generate any real pressure. The throttle plate has to be open, and the engine needs to be burning enough gas to produce enough exaust gas velocity and volume to spool up the turbo at sufficient speeds to produce pressure. If you have a vacuum/boost guage, you will see it go from deep in the vacuum part and up to 0 or so. So the boost doesn't really go anywhere because it doesnt really get generated. Hope this helps you understand the idea.

John