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wlit
06-08-2008, 02:16 AM
I just install Prosport Electrical Gauges and was wondering is the reading is right. I have 07 WRX, the picture below is when the car in idle. Isn't suppose stay in zero instead of -20? I believe all the wiring I install is correct. Anything wrong on using the supplied T?

When the car is on boost at about 4000 rpm in 3rd gear. It's only goes up to 5-7psi. I don't think that is correct. What is wrong with my set up? Thank you! :confused:

http://photos-e.ak.facebook.com/photos-ak-sf2p/v291/5/23/18413514/n18413514_34568628_8926.jpg

http://photos-f.ak.facebook.com/photos-ak-sf2p/v291/5/23/18413514/n18413514_34568629_9242.jpg

Prosport Gauges
06-08-2008, 05:21 AM
When the car is idling you are producing vacuum, and 20inHg is completely normal.

wlit
06-08-2008, 02:55 PM
I hardly able to reach 10 psi, could someone found out what it take to reach 10 psi? What gear and in wht rpm? Thank you in advance.

Gadget_B1
06-08-2008, 03:51 PM
try running in first and second but don't shift untill like 6500 RPM also give it full gas and see if that gives you a higher number. But mostly it depends on how much throttle you are giving it and how high your RPM's are. If you don't give it full throttle you won't get full boost.

darksc00by
06-08-2008, 03:55 PM
try it in 3rd and 4th. Typically it doesn't boost over 10lbs on a stock tune in 1st gear.

wlit
06-08-2008, 10:50 PM
try it in 3rd and 4th. Typically it doesn't boost over 10lbs on a stock tune in 1st gear.

I don't think much boost will generate in 1st and 2nd gear. I see close to 10 psi, when I drive in 4th gear with 75 mph @ about 4000 - 4500 rpm. Seem right? Does different supply T will make the different?

zen_nation
06-10-2008, 05:21 PM
thanks 4 the pics i did not know how my set up was untill i read your trend. i found a pinch in my line. i hope that solves my problem. thanks again.

skingfreak
06-10-2008, 06:23 PM
OP: take your car and get to 3k rpm's in 2nd gear and floor it (full throtal) untill redline, watch the boost pressure during that proccess. than report back here with your findings.

zen_nation
06-10-2008, 06:51 PM
i don't know what all that extra lines is doing all stuck together i just have a one perfect length hose may be you have to many hoses connected to each other to make one long hose and could be add some restriction on the proper reading. oh yeah don't ask me what that length is the line just measure yours and get a singel pice line.

hwy61
06-11-2008, 07:50 PM
My vac/boost gauge isn't hooked into the BPV. Is this a good place for the OP to be measuring boost? I would think off the intake manifold would be better. Is it possible for the BPV to be leaking or opening and not giving a good reading right in this vicinity?

Boost is made when the engine is under load and with adequate rpm. Running up the engine in 1st and 2nd gear allows the quick revving engine to suck in much of the boosted air the turbo is creating. Much higher boosts are easily seen in 4th gear as long as your speed is such that the tach is over 3,000 rpm when you floor it. In some instances if your boost management isn't set properly or your wastegate not opening at the proper psi, your boost will spike causing a fuel cut. This is almost impossible to make happen in 1st or 2nd gear though. Too easy sometimes in higher gears.

Try a run up the highway in 4th gear, start at 3,000 rpm and hold the throttle wide open. Then let us know what your boost is reading. 10 is too low even when stock. What should it be on a WRX, stock, 13 -14 psi...I don't remember. Hwy61