I'm not the best one to responed to this question but here's my thoughts.
Obviously, a car in stock condition does not have to have a turbo guage or else it would be a standard feature. However, it may not be a bad idea. The reason for having one is so you can make sure you're either boosting enough or not boosting too much. Boosting too much can be harmfull to your engine. Not boosting enough is just not as fun or fast.
If you make any mods (i.e. mbc) that may affect the boost made by the turbo, it is a must that you have a turbo guage.
The boost gauge is actually just a throttle position meter. It shows you how much throttle you are using and if you can floor it more. I hit the pedal to the metal so much that the boost gauge is pegged at 30 psi all the time, that way my mullet is flying through the air! I miss my firebird........
No, you don't really need one, but if you have a manual boost control, and you intend to push up the boost, its good to know whats happening, otherwise it could be an expensive exercise when you destroy the engine/turbo/gear box or clutch. As a stock car can only take around 17 PSI safely.
Even though a boost gauge isn't absolutely necessary on a stock WRX, as has already been pointed out, what it does do is allow you to monitor the "health" of your engine.
By being able to see not only your boost pressure, but also the vacuum present at idle, you may determine when performance is falling off and possibly locate a potential problem before it costs big $$$.
I know this is a little ambiguous, but I'm trying to jump-start your thought process. Look not only at the most obvious reason for installing a boost gauge, but also it's use as a on-board diagnostic tool.
Try a search on "boost" + "normal" + "pressure" and see what you find.
if i just buy boost gauge, only one ..........
how can i mount it near the steering wheel like the standard WRX w/ boost gauge on it ?
i just wanna buy one gauge i guess
don't have enough money for the gauge pod too
which one is the A pilar pod?
i know the OEM WRX gauge pod that replace the clock is around $75
i saw it yesterday somewhere
but it has holes for 3 52 mm gauges
i just need one for the moment
looking forward to buy morette and 22B spoiler
The A pillar pod is the one that runs down the left side by the windshield. That is the A pillar. The B pillar is the part that is between the front and rear doors and the C pillar is the one at the back of the car.
I wouldn't waste your money on morettes and a wing if you say you don't have any money. You will need new tires first.
You can get by without the cheap nylon tubing kit by piecing together parts from an auto parts store. The end result is much nicer than the tubing kit. I ended up re-doing mine a few weeks later w/o the nylon tubing.
You'll also need to modify the mounting bracket a bit (hammer it) and drill some holes in the bracket and the steering column to mount it properly, but it's really not that hard. Just take your time. It took me and a friend about an hour start to finish.
The best gauges to get are totally up to what you are going to do with the car. If you are going to leave it bone stock then you don't really need any. If you are getting a boost controler the the bare minimum would be a boost gauge but you could have problems with the exhaust getting too hot which pretty much everyone does who just runs a boost controler so you will want an EGT gauge as well. The third one is totally up to you. Either oil pressure or oil temp is good.