Stock Boost Gauge

[Danse Macabre]

Why is the stock boost gauge so wrong? What is it connected to? Im just curious.

 

[Enigma_Man]

The boost gauge isn't really "connected" to anything other than the ECU.

From what I understand, the ECU estimates boost by doing a quick bit of math with the incoming volume of air, temperature, and RPMs, I think. This inherently just sorta makes thigns more difficult to get right.

I have an Autometer gauge hooked up, and the stock boost gauge isn't really wrong... It follows along with the Autometer one pretty well. But try reading the difference between 10 or 11 or 12 psi on the stock gauge, it's not accurate enough. Also, I noticed that when I had the boost up to 15 psi on my 14b, the stock gauge doesn't seem to even go up to the 14 mark.. It never seems to reach it on my car.

So, if you're going to be altering your boost at all, you definitely need an aftermarket one. It has measures for individual PSI, and you know it's measuring actual boost, instead of calculated.

Hope that helps
-Jesse