Boost gauge question

[phaseoneracing]

Hey guys. I have an autometer boost gauge. Just plain boost not the one with the vac also. I hooked it up to the vaccuum hose where it showed on vfaq. But it doesnt move. Am i supposed to hook it up somewhere else? Thanks

 

[scott91370]

It didn't move when you started it or when you drove it and went wide open throttle?

At idle it won't and until you get into boost, it won't. You'll need to drive it and make sure you build boost before it will do anything.

 

[97gst_spyder]

Did you 'T' it with the FPR, or 'P' port on the TB?

Like Scott stated, how did you test?

 

[9!'clipseDOHC]

If you installed it on the FPR line, make sure that it's on the manifold side of the line.

 

[eligst21]

Yeah, like stated, make sure its on the manifold side of the fpr line. Also, without the inhg (vacuum) side of the boost gauge, it wont move at all on start up. If it only shows the boost, then you have to be boosting for it to move. So, go drive it and see what happens.

 

[Achelea]

The boost gauge you bought is for supercharged applications, not turbocharged. You need one with vacuum on it as well, cause you WILL throw that gauge's calibration off when you go into vacuum. Like during non boost driving, engine braking, etc etc.

Also, you kinda wanna see where your idle vacuum is to see how your system is doing. IE If at idle your car runs rough, your gauge won't tell you anything, one with vacuum on it might show you idling at 5in/mg instead of the usual 18. means boost leak.

Swap that one out, cause you'll be replacing it soon anyways.

 

[phaseoneracing]

I know it wont do it at idle. but i did rev it up a decent amount. Nothing too crazy for the motor. When does our boost start? what rpm? ill have to take it for a ride tomorrow. i do have a guage with a vac too but i like the autometer c2 better ha.

 

[Achelea]

I know it wont do it at idle. but i did rev it up a decent amount. Nothing too crazy for the motor. When does our boost start? what rpm? ill have to take it for a ride tomorrow. i do have a guage with a vac too but i like the autometer c2 better ha.

When you're in Neutral? Around 7k. Without a load on the engine the waste gate won't close and send exhaust through the turbocharger.

When you're driving it starts building around 2k, and full boost around 3000-3500.

As for the gauges, the reason I say you will break yours is look at it this way. See the little pin that the needle rests on before it goes into boost? That's your elbow at full extension. When you down shift and go into engine breaking, that's jet Li breaking your elbow backwards. The negative pressure is pulling the needle against the pin. If the pin doesn't end up turning on it's shaft, the bellows inside might get damaged. Extreme example, but there's a reason the factory gauge shows positive and negative.

Also, Done a Boost Leak Test recently?

Wait a tic.. I need to do one too. ^.^;

 

[Gostlrs]

I never seen a boost gauge that is for supercharger only.....? Is that like having a left handed screwdriver?

 

[Achelea]

I never seen a boost gauge that is for supercharger only.....? Is that like having a left handed screwdriver?

Think about it.
Turbo chargers have to spool up, and it's possible to run out of boost.
Superchargers are mechanically driven. They are always on.

And I guess. They have left handed threaded drill bits.

 

[Gostlrs]

Think about it.
Turbo chargers have to spool up, and it's possible to run out of boost.
Superchargers are mechanically driven. They are always on.

And I guess. They have left handed threaded drill bits.

Ummm i really dont think you have an idea what your talking about...

YouTube - ‪Scion tC Defi Gauges- supercharger 2‬‏


There is no such thing as a supercharger only gauge...Every car can read Vac.

 

[Achelea]

I stand corrected then. ^.^

Either way.. I'd get a gauge with Boost and Vacuum.

 

[Gostlrs]

Agreed, on both counts..