question on stock WRX turbo gauge

pehavens · 05-29-2002, 06:28 PM

Can someone give me an explanation ...

I have the optional turbo guage installed by the dealer and I am not sure how to read it. Often I have seen posts describing the boost level in number between 12 to 16 or more (I am assuming this is PSI). The guage I have ranges from -.1 to .15. The highest I have seen it is about .9. Everything else is stock on my WRX. Can someone tell me how to convert this? And why is it negative at times?

Another question I have. I am not sure why the turbo only spools up for a second when the throttle is pressed and the transmission is not engaged. Does this mean that the turbo fan only spins if the car is in gear. What exactly is being messured by the guage? Is it the pressue inside the cylinder?

If you know of a good place me to learn about all this I would greatly appreciate it. Thanks.

-Pete

* Registered users of the site do not see these ads.

MAD REX · 05-29-2002, 06:52 PM

Do a search before you post

MPa Bar psi
0.01 0.1 1.45
0.02 0.2 2.9
0.03 0.3 4.35
0.04 0.4 5.8
0.05 0.5 7.25
0.06 0.6 8.7
0.07 0.7 10.15
0.08 0.8 11.6
0.09 0.9 13.05
0.10 1.0 14.5
0.11 1.1 15.95
0.12 1.2 17.4
0.13 1.3 18.85
0.14 1.4 20.3
0.15 1.5 21.75

pehavens · 05-29-2002, 07:13 PM

Thanks for the numbers MAD REX. I did search several times but came up empty.

Anybody able to explain the spool up blip when out of gear or the negative numbers on the guage.

Thanks,

-Pete

peczenij · 05-29-2002, 10:01 PM

A boost gauge is actually a dual gauge.
The negative numbers are vacuum (suction) and the positive numbers are turbo boost (pressure).
A vacuum condition is caused by the throttle only being partially open, making the engine “suck” for air.
A normally aspirated engine (no turbo) will go from negative to zero vacuum at wide open throttle.
A turbo actually pressurizes the incoming air creating boost.
Most cars use the vacuum provided from the engine to provide power to accessories such as power brakes.
Enjoy…

.080=11.6 PSI
.085=12.3
.090=13.1
.095=13.8
.100=14.5
.105=15.2
.110=16.0
.115=16.7
.120=17.4
.125=18.1
.130=18.9
.135=19.6
.140=20.3
.145=21.0
.150=21.8

05-29-2002, 06:28 PM	#1
pehavens Scooby Newbie Member#: 11821 Join Date: Oct 2001	question on stock WRX turbo guage Can someone give me an explanation ... I have the optional turbo guage installed by the dealer and I am not sure how to read it. Often I have seen posts describing the boost level in number between 12 to 16 or more (I am assuming this is PSI). The guage I have ranges from -.1 to .15. The highest I have seen it is about .9. Everything else is stock on my WRX. Can someone tell me how to convert this? And why is it negative at times? Another question I have. I am not sure why the turbo only spools up for a second when the throttle is pressed and the transmission is not engaged. Does this mean that the turbo fan only spins if the car is in gear. What exactly is being messured by the guage? Is it the pressue inside the cylinder? If you know of a good place me to learn about all this I would greatly appreciate it. Thanks. -Pete * Registered users of the site do not see these ads.

05-29-2002, 07:13 PM	#3
pehavens Scooby Newbie Member#: 11821 Join Date: Oct 2001	thanks Thanks for the numbers MAD REX. I did search several times but came up empty. Anybody able to explain the spool up blip when out of gear or the negative numbers on the guage. Thanks, -Pete

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
question on driving WRX/ turbo cars	Cata	Vancouver Impreza Club Forum -- VIC	13	01-02-2005 04:26 AM
Max WHP on stock WRX turbo	wRxbeater11	Proven Power Bragging	35	02-28-2004 01:48 AM
Max Boost & HP on Stock WRX Turbo	noob	Newbies & FAQs	4	12-21-2002 06:19 PM
Fastest Spool-Up on Stock WRX Turbo?	WRacerX	Factory 2.0L Turbo Powertrain	33	07-05-2002 06:38 PM
Question for those running stock WRX turbos on RS's	STiTuner	Normally Aspirated with bolt-on Forced Induction Powertrain	13	04-26-2002 08:43 PM

05-29-2002, 06:52 PM	#2
MAD REX Scooby Specialist Member#: 18163 Join Date: Apr 2002 Location: Denver Vehicle: 2002 2.5 WRX MBP	Do a search before you post MPa Bar psi 0.01 0.1 1.45 0.02 0.2 2.9 0.03 0.3 4.35 0.04 0.4 5.8 0.05 0.5 7.25 0.06 0.6 8.7 0.07 0.7 10.15 0.08 0.8 11.6 0.09 0.9 13.05 0.10 1.0 14.5 0.11 1.1 15.95 0.12 1.2 17.4 0.13 1.3 18.85 0.14 1.4 20.3 0.15 1.5 21.75

05-29-2002, 10:01 PM	#4
peczenij Scooby Newbie Member#: 16791 Join Date: Mar 2002 Location: Pennsylvania Vehicle: 2004 WRX STi WRBlue	A boost gauge is actually a dual gauge. The negative numbers are vacuum (suction) and the positive numbers are turbo boost (pressure). A vacuum condition is caused by the throttle only being partially open, making the engine “suck” for air. A normally aspirated engine (no turbo) will go from negative to zero vacuum at wide open throttle. A turbo actually pressurizes the incoming air creating boost. Most cars use the vacuum provided from the engine to provide power to accessories such as power brakes. Enjoy… .080=11.6 PSI .085=12.3 .090=13.1 .095=13.8 .100=14.5 .105=15.2 .110=16.0 .115=16.7 .120=17.4 .125=18.1 .130=18.9 .135=19.6 .140=20.3 .145=21.0 .150=21.8