I just wanted to post the results of a simple test I performed last night. My PFC always read about 1 to 1.5 PSI lower then my Autometer boost gauge but I suspected this was do only to the offset to I decided to check it with my mityvac.

First I changed my offset to 3600 to zero the factory sensor. I live in Florida so I'm at sea-level. Boost used to read -24 to -26 without the engine running.

Next I hooked up my mityvac to the boost sensor & pumped it up to 10PSI. The commander read .69 (a hair low), then I pumped it to 14PSI. The commander boost reading was at .98 (dead on!). Then 15PSI, commander read 1.05 (dead on). 17PSI equaled 1.19, & the commander wouldn't read any higher then this. (I pumped it to 20PSI & the commander still read 1.19)

Anyhow, with all the threads here about the commander reading as low as 2PSI I just figured I'd post my test results, & recommend that everybody get a Datalogit & adjust the PIM offset to zero the gauge.

Eric.

 

That is very good info. Thanks for posting your test results.

 

what is this offsetu are referring to??

 

It's in the Datalogit, on the Settings 3 tab.

 

i see..thanks
I dontr have the dataloggit. but i believe my power fc reads 0 boost with the engine off..does this mean i am seeing good boost numbers as measured by the pfc?

 

You can always hook up another boost gauge to compare it to. Or a pressure hand pump to pressurized the sensor & check the accuracy...