rjparth

I'm happy with my tune, but wondering what it would take to datalog accurate MAP readings on my FI car using HPTuners. Does the tune need to change if installing a 2 or 3 bar MAP? If so, I'm assuming a 2 or 3 bar sensor reports MAP differently (i.e. 0.2v = X on the stock MAP, but Y on a 2 or 3 bar)?

Big Al

iTrader: (1)

Here is an easy way to look at it. A one bar sensor uses 100% of its range to report atmospheric pressure. Two bar, 1/2 scale or 50% of the range would be atmospheric, the rest is reporting boost. Up to twice atmospheric pressure. So you have to rescale the PCM. 3 bar, same thing except atmospheric pressure is only 1/3 of the range. So a two bar sensor has 1/2 the resolution of a one bar sensor, but can report twice the range. Atmospheric pressure is about 14.5 PSI, so a two bar would be fine up to 15 pounds of boost. For you hair splitters one Bar is actually 0.9869 atmospheres. One atmosphere is 14.6956 psi.

BTW: The best MAP sensors I've found are genuine GM.

Al

robbyredneck

iTrader: (1)

if your asking about the scanner then. delete the sae map pid and insert the 2bar pid. it's that simple then you can set up a histogram to measure and plot boost. this is providing you have a 2bar map and are in 2bar sd os.

rjparth

Makes sense. On the HP Tuners, are there any add-ons needed to recalibrate the PCM for 2 or 3 bar?

robbyredneck

iTrader: (1)

as far as addons not really but you use credits to upgrade to 2 or 3bar os which in turn doubles or triples the map range in your tables. you can't just plug a 2 bar map in.

in the editor . engine diagnostics>airflow>map sensor linear and map sensor offset. this adjusts your working range and scale.

none in the scanner that i know of unless you user define.