Question for Innovate Lm1 users logging boost

[Lhorn]

I got a 3 bar MAP sensor to log boost with my LM1 but am getting odd readings (using rpm convertor, not auxbox) . When setting up the channel that you want to log on, what parameters do you put into to tell the computer how to imterpret the data (ie x volts = y lbs boost). I grabbed some numbers off of their message board but when I did a log, the Boost numbers were entirely erratic. When my VDO boost gauge would read 12lbs boost, the LM1 was reading 4 for example. Also the graph of the boost channel was completely erratic. Any advice? Have you been able to log boost successfully?

Thanks

 

[Lhorn]

To add another question, when the car is sitting at idle, do I want my log to read boost as zero or do I want it to read the real pressure which is the engine's vacuum (-14 or whatever)?

 

[turbojimmy]

It's been a while since I did it, but I think I just put in whatever the barometric pressure was that day and it worked. Innovate's documentation on this stuff is very good. If you don't have it you can download it from their site.

Jim

 

[Lhorn]

I'll check the documents that came with my stuff, but I've already look at it and didn't understand. I'll check again.
The way I understand it, when you configure a channel, you set 2 values, and the software creates a curve (x voltage = Y PSI). I actually hooked the MAP sensor to an airtank with a known air pressure and measured the voltage. Also checked voltage without no pressure (ie not connected to air tank). I put these values in and when I started the car at idle, it read -13 or whatever. I guess that is my vacuum. Instead of "0 pressure = x volts" I should have put in the "barometric pressure = x volts" as one of my data points. I'll do some more reading.