Another Boost Gauge Question

[tom1995tsi]

Should my boost controller be reading vac when im at low rpms i dont hear the turbo or anything but shouldnt it be giving around 2-3 even at 2 1/2k rpms? I still dont know if my 16g is running at 15 psi or not w/o a mbc. It just doesnt seem right.

 

[Jason_99ozGS]

I am going to assume you meant boost gauge and not boost controller. Yes your boost gauge will read vacuum at low rpms. It will actually read vacuum anytime you're not on the gas or if you're on the gas very little. For example at idle the gauge should read around 18in/Hg and when decelerating it will read around 22in/Hg.

To find out if your 16g if giving you 15psi or not take the car up to 40mph, floor the car and look at the boost gauge.

 

[tom1995tsi]

I know it is saying 15 psi but i dont know if the gauge is accurate how much hp should i have running 15 psi? with a 16g, K&n intake, and a performance muffler and ngk spark plugs?

 

[Phaze2ECU]

Thats a very general question man, odds are if the gauge sits at zero when the car is off its near accurate. Isnt stock like ~12psi so i cant imagine youd be at an insane power levels but it should def feel better then stock.

 

[tom1995tsi]

Yea the 16g is quite a bit faster than stock but it sometimes jumps up to 16-17 psi and my worry is that if it right the stock bov would be leaking and the boost would actually be at 17.
I guess the only way to find out is get a mbc and a 1g bov. My idea was that my pre-engineering teacher knows alot about pnumatics and im goining to ask him to hook the boost gauge up to another meter to see if it is accurate.