Sense check please.

Trying to sort some serious issues with a tune on a mates VXR8. The KPA is reading REALLY low. 120kpa for what should be 190KPA at least.

He has the GM12592525. Am I right that the settings on this is

315.5 for the scaler
The offset is 1.1

Although we can change the offset to fine tune the MAP sensor if its not quite right?

Any confirmation would be great.