Which is more accurate?

[nismo tuned s14]

I have an Auto Meter boost gauge that has been on my 96 KA-T for the past few years. I have it T'd off a line that hooks up to the nipple on the intercooler piping. I recently bought an electronic boost controller. The pressure sensor on that T's off from the FPR line.

My Auto Meter boost gauge doesn't read vacuum, only boost. I hooked it up to the FPR vacuum line, and it didn't read vacuum or boost. The boost controller reads both boost and vacuum. When I boost hard, the Auto Meter gauge seems to be about 5+ PSI higher than what the boost controller reads.

I just wanted to know, which should I trust more?

[garagelu]

I actually blew up 2 engines because of a cheap autometer boost gauge. When I set my boost controller up, I had the settings at 14 and 18 psi according to the boost gauge. After I installed my last engine, I decided to go tune it thinking it was the tune on it that was bad. Luckily my tuner with a dynapack has a hookup for boost. Found out I was boosting my engine at around 24 psi when I had my boost controller set on high boost.

Pretty funny huh? I will never buy autometer products ever again nor will I ever recommend them.

[nismo tuned s14]

I'm sorry to hear that man. I guess I'm lucky that mine seems to be reading higher boost than what it really is. There was something that never seems right about that boost gauge, especially after finding out it wouldn't read vacuum. I bought it way before I knew that people had lots of problems with them.

[unicoladron]

what brand is your electronic boost controller?

and regardless of what gauge installation directions/controller directions say, i personally wouldn't trust T-ing off of the FPR vac source.

since your boost gauge doesn't read vacuum, i would use the nipple on the bottom of your throttle body since i believe that is just a boost source (i could be wrong) and use the nipple on your IC piping as the source for your controller.

but...yeah depending on wh ether or not you have a crappy ebc, i would say average up the two readings and there's your psi reading lol

[nismo tuned s14]

I have the GReddy Profec E-01. It said to T off the FPR line. So I should try the line under the throttle body?

[unicoladron]

I have the GReddy Profec E-01. It said to T off the FPR line. So I should try the line under the throttle body?

not for the boost controller, but for your autometer.

but i've never heard of greddy's quality being questioned, so yeah newer + better reputation = more accurate reading?

yeah, i'm sure tons of people run with T's on their FPR vac line, but something about that makes me uneasy.

connect the profec to the IC nipple and don't T it or anything.

[nismo tuned s14]

Sounds good. I think I tried that when I first installed the boost controller, but I don't think it worked because I had other vacuum lines switched. If anything I'll be able to tell if the E-01 and the Auto Meter read the same when I hook it up to the intercooler nipple. Thanks man.

[steve shadows]

Autometer are piles of shit

Mine shows up like 21 psi sometimes on higher load runs, like 4th gear on the Highway.

My Data log on my 3 Bar GM MAP sensor hooked up to the Haltech reads out logs at 17-18 psi max! :ugh:

This was confirmed with the Dyno clandestine MAP as well and other external MAP sensor for pressure we use for diagnosis at the shop.

The autometer was like 2-3 psi over all the time on hold

It's garbage, but it does let me know when I am spiking way too high (which really doesnt happen anymore because of the sharp tune on the closed loop function with the E8).

I am going to grab a Defi or other unit eventually.