1. I didnt calibrate it wrong, I didnt calibrate it at all, I just plugged in a close enough value. At most I would be off my .3psi, not 1.5-4psi. Razorlab didnt show me anything, because there isnt anything to show.

2. If the full logs showed any bit of useful info I would have posted them, but they didnt. AFR was imcomplete and I'm not at liberty to post my timing maps
3. Get off the who log deal, really. Ill post them soon enough, I simply didnt have solid log to post. I simply left off the other logged values to clean up the graph, since this post WAS ABOUT THE BOOST SENSOR. Adding in other values throws off the scales and such, and it at the time of positng, I didnt see how it was relevant to HOW THE BOOST SENSOR IS READING.


I came here for help, it was not to gloat and brag how I'm hitting 27psi+, then be attacked, that was not my intention at all considering my boost target was <23psi. If that was the case, I would have started my own thread "Hey look at me running 27.5psi on cali pump *zips up flame suit*"

Seriously man, I really am at a loss right now why you are ****ing attacking me. Jesus christ lay off yeah?. Mrfred,razorlab, and others are here to help and have given me some insight, I even posted a second log of how I corrected the overboosting issues and how its now reading on par with my original boost targets as logged on 2 different dynos (one being razorlabs). You seem to be here to naysay, attack, and preach off your all mightly all knowing soap box so excuse me for not giving into your RUDE demands.

 

Just for reference. To show im not hiding anything, that I was really just looking for help with any possibilities that the sensor may be grossly off. I was not hitting my target timing accross the board due to going into higher load cells. Obviously the car knocks with the boost it was hitting in higher rpms. No negative timing as you can see

 

Hey Guys,

There's definitely some strong opinions flying around here which I can understand. I get pretty heated up about this as well. However, I don't want this thread shut down. If you guys can tone it down a bit, that would be great.

 

np fred. Im really wasnt trying to start any trouble or a flame war or anything, i just felt like I was needlessly being attacked. Got busy tonight so the second gauge will go in tomorrow instead. Logged my 2-byte. At 27psi I was getting 280 peak loads, at 23-24 now im getting 260ish

Did the power graphing feature, registered at 371hp/331ftlbs for a 3rd gear pull. Used 3200lbs, 175lb driver weight, 70F. Didnt change the gearing

Seem on par with other cars?

 

I just got off Razorlab's dyno the other day and it says i am only boosting 21.XX and I will do more logs but last one said 22.5X and I am at sea level - my JDM sensor reads correctly when engine is off but car is on = 0.00Xpsi. Hope this helps.

 

ic ic. I think he said his jdm map read dead on with his zt2 while on the dyno, so the difference you see might not be sensor to sensor, but road vs dyno. On the road you are going to have more air/higher loads so likely more boost. I logged it again tonight and it creeped to 24psi. Only intermiten 1 knock counts however

 

Once in a while a little emotion keeps this geeky stuff interesting...

To a point of course.

 

mrfred,

I hooked up my GMMAP sensor and read the number recorded with the igintion on and engine off. It was 0.1. My JDMMAP sensor reads 0.03. I do not think they are too far apart.

 

But the GM is higher

 

I highly doubt that a 0.07 difference would lead to about 1 psi variance between the sensors.

Here is what mrfred said about the subject:

"You can also log with the ignition set to "ON" but with the engine off. The MAP sensor should read 0 psi. If its off by more than 0.2 psi, you can change the offset in the EvoScan formula. e.g., if you see -0.5 psi with the engine off, then change 14.51 to 14.0. People within 1000 feet of sea level shouldn't need to do this, but people at higher elevations (CO, NM, UT, etc) may want to check this."

https://www.evolutionm.net/forums/sh...2&postcount=45

As you can see the the GMMAP sensor is not off by more than 0.2 psi. The difference between the two sensors is 0.07.

 

it was a joke

anyone log boost via GM map through the 0-5v user input on the zt2?

 

I logged the JDMMAP sensor with ignition on and engine off and it fluctuated between 0.0372 and 0.1897. I logged the pattern. It is attached. Any idea why it does that.

I wanted to log the GMMAP sensor but Logworks would not allow me to log with the engine off and ignition on.

On the Innovate digital gauge, I did notice that the numbers fell from 0.1 to 0.07 after a while.

 

What software/hardware did you use for logging? You use several different combos, so I never know which one you are using.

 

The attached file says "EvoScanDataLog"

 

The fluctuation between 0.04 and 0.19 psi is due to the combined effect of two things:

1) When the MAP sensor signal is read through the ECU, it becomes digitized. A 1-byte variable is used to describe the boost signal, so the full range of the sensor is descritized into 256 steps. Since its a 3 bar sensor, the step size is roughly: 14.5*3/256 = 0.17 psi. Any MAP sensor signal routed through the ECU would show this.

2) Under the atmospheric conditions when you took the log, the analog signal from the MAP sensor going into the ECU is right in between two steps, and minor fluctuations in atmospheric pressure are causing the signal to bounce back and forth between the two steps.