What's up with the stock Boost Gauge?
 

Apparently, everybody hates the stock boost gauge because it's no good. I run 7 lbs of boost, and for some reason, the stock gauge reads what looks like should be 20 lbs *1/2 way between 0 and 40.* Though, they may be completely different numbers, that's besides the point to me :P I wonder why Mazda didn't put a more reliable boost gauge there so people didn't have to go get an aftermaket one...

Because on a stock car it is just there as a toy. Also the stock gauge is not in PSI, i belive it is in cmHg or mmHg x 10. So 20 means about 4psi.

But that gauge is so inacurate.....

The stock boost guage is actually a good quality electronic gauge. Just if your car's electrical is not working right it will have problems.


BTW: The FD has no boost guage at all.

Lucky FDs. What's the equation to convert the mmHg to the PSI? How did you go from 20 to 4?

Aha! Thanks. That definitely cleared that up. :D

It says on the gauge what the units are. What did you think that writing meant? ;)

Why would they? Manufacturers don't make cars to be modified. The gauge works fine for a stock car, and that's all it was designed to do. Can you think of any car with a boost gauge good enough to use on a modified car?

Seriously, he's kinda right. The car was manufactured for the US market...proven by the "MPH" speedometer. Yet they couldn't alter the boost gauge to read "psi" to suit this same market? They tailored the rest of the car for us...emissions, lighting standards, crash standards.

Even if you look at it from the japanese perspective, I believe they tend to use bar or kg/cm^2 to measure pressure generally, right? So why do THEY need to see mm/Hg measured? Even if you use the argument that the car is sold for what it is and not meant to be modified, why shouldn't the driver be able to see that he is boosting 6psi instead of however many mm/Hg?

Yea that is true and the should have had aleast some other markers instead of just 0 and 40 because then you kinda just guess where it is.

Yeah, I don't like doing angles/conversions while driving. :p

Because 20 of something sounds much better than just 6!

Maybe for the same reason that some cars have the numerals Italicized to give you the illusion it is much faster :)

Vince

SRT-4 :) Uses a Autometer 30inHg/20psi gauge. Although the '03 batch were all junk.

But I asked for one good enough to use on a modified car... :p:

Doesn't mm/hg = millibars? I'm no math whiz or anything.

Nope.

mmHg = millimeters of mercury, i.e. how high mercury is pushed up a U-tube if pressure is applied to one side. 1mmHg = 133.3Pa

1 millibar = 100Pa

:)