I recommend that you check your boost levels with an accurate gauge or log knock sum, octane, and ignition advance with EvoScan. I did the latter and observed some pretty big knock sums. On one run, the knock sum spiked to 15! I'm working with Vishnu now to get the boost level reduced a bit.

 

That has been my experience as well. I had a Defi D and it would tell me that the boost was around 23-23.5 psi, but when I installed my MAP sensor and logged my boost it was at 22 peak and tapering to around 18 by redline. The Defi D read 1-1.5 psi too high. I sold the Defi and now I am running an Innovate XD-16 off of the Map sensor.

 

What is your AFR and timing like along with your boost?

 

My oem gauge reads low!

here is how my oem boost gauge compares to our druck pressure measurement device.

We use the druck as our standard & is sent out regularly for calibration, so i will hang my ***** on its accuracy.

In saying that, i used a cheapo mennier hand held pressure / vacuum gauge & compared it to the druck 3 times to confirm repeatability, took the hand held device to the car to see what the oem gauge read.

Below are my '03 oem evo boost gauge.

 

I'm not running a wideband, so I have no actual afr values, and its a vendor flash, so I'm not supposed to share afr and timing data anyhow. I can say that a huge amount of timing was pulled on the run when the knock sum of 15 occurred.

I'm thinking that I need to install a MAP sensor and meter. What MAP sensor are you using? Do you know if that Innovate gauge will fit in the stock Evo boost gauge plate?