3 bar map sensor?

[hongkongstuey]

heard talk of these on some of the u.s. forums, what do they do? heard that some of the more powerful pd engined vw's have a 2.5 bar sensor?

did a few conversions at work through convert . exe and got the figures worked out for my car

did some logs on vag com and came up with the following info.

my car reads 2091mbar absolute pressure at 3 times during the log

2091mbar ( 2.091bar) into psi is 30.3 psi
so mines kicking out 2.091 bar of boost

does it read atmospheric pressure at 1bar and then adds the turbo pressure or is the figure the total?

30.3 psi is a bit much for a small turbo and think its running it a bit near the limits, would a 3 bar map sensor help in keeping everything reading properly or will it just allow more boost by fooling it, i dont want any more power with standard clutch etc ive just heard people are fitting them to remapped/chipped cars. hope someone knows any of the answers.

what is the standard psi/bar for the standard set up on a non mapped/chipped car?

certainly points to why mine has 158bhp from a 110 with all that boost!! :biglaugh:

[ini]

The standard 2.5bar map includes 1bar of atmospheric pressure, giving 1.5bar to play with.

This means your standard TDI 2.5bar map can measure approx 14 - 21psi (1 - 1.5bar) with the 0-5v signal stretched over that range.

3bar maps are used when steady boost of more than 21psi is required, and allows the ecu to 'see' and regulate the higher boost pressures upto approx 30psi.

A 3bar map must be calibrated or accounted for in the mapping, otherwise it will report lower manifold pressure than 'actual', resulting in potentially damaging higher boost levels.

[NickPicks]

Yes, I think the MAP stands for Manifold Absolute Pressure. Absolute pressure is measured relative to a vacuum, so at normal atmospheric pressure, your map sensor will read 1 bar.

If you're up a mountain, it'll read lower, and if you visit the dead sea, it'll read higher.