The MAP sensor is only for the boost gauge in stock setups. Unless you have aftermarket fuel injection or some other devices that requires boost measurement, I don't see a reason for it.
Stock is 2 bar 1 for 14.7 inches of vacuum, 1 bar for 14.7 pounds of boost on the analog dashes. The digital dash cars didnt get a map sensor because they didnt have the boost bar on the dash. Just 2 idiot lights with a hobbs switch.
Aftermarket or TTA 3 bar same as above but 2 bar is for up to 29.4 psi ...
The reason the TTA had a 3 bar is because it came out from the factory running 16.5 psi and the 2 bar wont work in that application.
The TTA boost gauge would read to 20 on the dash.
Hence GM making it. Maybe for the callaway vette too, i forget.
BW
