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I have one serious question, please excuse my ignorance and give me a constructive answer if one is needed :) Why do most of us want/need an aftermarket boost gauge? The factory item goes up to 1.5 bar, and I and probably most others don't plan to run much more than 1 bar without some serious engine mods, so why do so many people want aftermarket gauges?

I had one on my car when I got it, but it was half-blocking the tacho and I found myself bouncing off the redline way too often because I couldn't see it! So I took it out, plugged up the extra vacuum line hole and have been using the dash one and the digital readout on the boost controller ever since. They both match up almost perfectly too. At 0.8 bar on the Greddy box, reading about halfway to 7 on the dash gauge.

JimX.

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Originally posted by JimX

I have one serious question, please excuse my ignorance and give me a constructive answer if one is needed :) Why do most of us want/need an aftermarket boost gauge? The factory item goes up to 1.5 bar, and I and probably most others don't plan to run much more than 1 bar without some serious engine mods, so why do so many people want aftermarket gauges?  

JimX.

I always thought the boost gauge built in standard on my dash just went to 7psi?

I have a Greddy Recall boost gauge. I have different options of how i wanna view my gauge. I can view boost in real time eg exactly what boost i am pumping out right now or i flick it to memory and it shows me the highest amount of boost i have used throughout my travel. Good for measuring how much boost i have coming through after winding up or down. It cam with the car but if you can get a Greddy recall boost gauge go for it it is pretty cool!

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The factory boost gauge is way too slow to react to quick changes and spikes. I certainally would use it to set your bleed valve.

Plus the factory boost gauge isn't in psi. I think 7 on he factory gauge is somewhere around the 14psi mark.

If you want a after market boost gauge that looks factory, have a look at the VDO range. The 52mm ones have -20 Vac through to 25psi, are black faced, black bezel, white numbers and red needle.

I think they are around the $150 mark each.

I have a twin A pillar gauge holder in mine with a oil temp and boost gauge from VDO, and I'm always asked it is factory cause it blends in well with the dash.

But I've been thinking about moving them down to under the stereo....... Hmmmmm, not sure yet......

J

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Yeah as Jay95R33 said the factory gauge isn't in psi, it's in 100x mm of Mercury, and 7 of those I thought was around 1.5 bar but after double-checking the formula it's actually around 1 bar (13.535746 psi to be almost precise). So at max boost I must be getting a bit over halfway on my gauge. Anyway even at 1 bar it's good enough for me for the time being.

Jay95R33, I agree it's pretty slow to change, but I've also got my digital readout on the Greddy boost controller which is pretty much instantaneous.

I dunno, I think I will take the one I removed from my steering column and mount it on the A-pillar one day, but for the time being I don't see it as an essential item. I definitely wouldn't use the factory gauge to set anything up to precision, but I think for general driving it's good enough. As long as you're running 1 bar or less :)

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Some of you guys pay mega bucks for guages! Far out.....

I just bought a Speco boost guage. Its white faced, has a silver rim, goes to 30 psi, and 30 IN-Hg vac. It cost me $62.

Also bought the Speco chrome cup to go with it, this was $40.

Not bad I thought, considering i paid about $150 for the autometre boost guage I had in my old ET pulsar, with out the cup.... :D

Steve

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| hype^ |, no. But I have an electronic boost controller with a digital readout, and a dial to set it from the dash instead of the engine bay. Sure I would use my Autometer gauge to set the boost if I had to use the bleed valve but I don't think I'd leave it in there permanently. It was certainly in the most ridiculous spot when I got the car on top of the steering column, if I put it back it's going on the A-pillar.

Just over half on the factory gauge is about 0.6-0.7 bar I'm guessing. Exactly halfway *should* be around 0.5 bar (7psi), but it could just be a margin of error in the boost gauge.

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MIC, a good way to do it is find an uphill stretch of road where you can load up the engine in 3rd gear. At 5000 rpm thiis is pretty quick so chose your road wisely.

HYPE, if you have the standard boost control (factory) you will get an increase in boost at around 4500 rpm to about .8 bar/11 psi/570 mmHg. Below that you will only get around 7 psi.

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