I have an autometer boost/vaccum gauge that reads 1psi of boost when the car is turned off instead of reading zero. Is it then a safe assumption to make that when the gauge shows say 21psi, I'm really pushing 20psi of boost? I would guess if that's the case the same would be true for the vacuum readings. Ex: if my guage says 15vac, then the car is really at 16vac. Has anybody else experienced this, and if so, have you ever switch out guages and notice that with a different guage it was reading the same pressure as the autometer but was zeroed like it should be.

Example:

Autometer; car off = 1psi of boost; WOT 21psi of boost, those numbers always being accurate with very little flucuation.

Different boost gauge w/out changing boost settings
car off = 0psi of boost, WOT 20psi of boost.

I hoping I was able to make sense. Basically all I want to know is if my boost guage is fine but just of by one psi, so that when my guage says 21psi, I know it's really 20psi.

 

One could assume that simply subtracting 1 will give you a correct reading, but if the gauge is already reading off with no power, there is no way to tell if the gauge is damaged to the point that other readings are incorrect.

Safe way, buy a new gauge.

 

Autometer's boost gauge isn't accurate 8 times out of 10 in my exeperience.

 

Ussualy they are off in a linear fashion like you describe, but if its reading 15 vacuum, it would be 14, not 16.

 

Wow, you've owned 10 of them? I should feel lucky that my one and only AM mech boost gauge reads accurately.

 

all 3 of the ones I have owned have been perfest, as well as any I have seen...

Bad ones do exist, but 4 in 5 is simply a lie.

 

Autometer gauges are one of the best US Manufactured gauges in the industry.. ProComp's SportComps, and UltraLite's are used in a majority of the vehicles in a majority of motorsports in the USA and many other countries.. However, the Cobolt, Carbon Fiber, and other "Trendy" versions of the gauges are based on the inexpensive Autogage line or Z-Series line of gauges, which are not as good a quality as their higher end gauges.

I have used nothing but Autometer gauges for the 20 years I've been modifying cars, and had only 1 defective gauge in the entire time, all were accurate unless they were modified or damaged by something. Check to make sure you didn't twist the bezel, on the inexpensive gauges, if you overtighten the fitting to the vacuum line on the back of the gauge, you can "shift" the needle slightly from zero..

There's always going to be a defective gauge, but I wish people would stop slamming american made gauges.. There are junk gauges, and good gauges.. you do get what you pay for.

http://bbs.overlord.net:9000/userpics/malibu_nov.jpg this car is supercharged, with approx 600whp, entirely instrumented in Autometer Pro-Comp gauges (tach, fuel level, and boost are sport-comp gauges)

http://www.bracketracing.com:9000/fe...ge_Cluster.jpg this is a closeup of the dash pod when I was fabricating it.. gives you a closeup of the gauges.

 

I came across a bad autometer gauge once with the same symptom, instead of reading 0 when car was off, it was 1 psi or something like that. I sent it back and got it replaced without any issues or hassles.

 

We are not fans of Autometer gauges at all! We had an Autometer boost gauge that was leaking to point where you could hear a lovely hissing noise coming from it. We took it out, pressure tested it and found that the boost simply leaked out. We then purchased a BRAND NEW Autometer boost gauge took it out of the box and pressure tested it. Leaked just the same. Took a Greddy gauge, pressure tested it and it held boost steady. To this day we just don't bother with Autometer gauges. We find that you just can't beat the accuracy and quality of a good Japanese gauge. Hell, maybe I can market the Greddy gauges to the NASCAR guys!

 

They won't pay 200 bux for a gauge whe nthey can pay 50 bux instead. lol.

If and when I get an EVO I have a choices in mind for gauges.

 

1 psi not bad. Miney says 15 vacum when the car is off. It means the gauge got uncalibrated. Im on my 3rd gauge because of that.