nope, it's all fine and dandy. I love my zeitronix unit

 

kewll....i'll do that to then

 

so, in general just hook the user input wire up to the MAP wire that the ecu reads from?

 

Yep. And the voltage/pressure table posted on h-t is excellent:

1760mbar=4.96v 11.022 PSI
1700mbar=4,80v 10.152
1600mbar=4,52v 8.702
1500mbar=4,25v 7.252
1400mbar=3,97v 5.801
1300mbar=3,69v 4.351
1200mbar=3,42v 2.901
1100mbar=3,15v 1.45
1000mbar=2,87v 0.0
900mbar=2,60v -2.953 in/Hg
800mbar=2,32v -5.906
700mbar=2,05v -8.859
600mbar=1,77v -11.811995
500mbar=1,50v -14.764994
400mbar=1,22v -17.717993
300mbar=0,94v -20.670991
200mbar=0,67v -23.62399
100mbar=0,40v -26.576989

Reprinted by permission of... oh, hell I didn't get permission.

 

So you guys are wiring a MAP sensor into the ZT-2 with no additional hardware? This was my primary requirment.. does it also read RPMs? If the datalogging could log the vacuum/boost, rpms, and afr it would be perfect!

 

the zt-2 reads lambda, afr, rpm, tps, egt (if you have a probe), boost (if you buy their $100+ boost sensor) and it has a 0-5V user input. What we're doing is using the user input to track the voltage of the map sensor, allowing us a sort of ghetto way to read our vacuum/pressure.

 

I installed my ZT-2 last night. Im successfully logging the stock MAP sensor very well. For OBD0 (im using a pm6), i tapped the White wire at pin C11. Works great! PM me if youd like to look at one of my logs with the MAP sensor.

 

Those of you who are using the map sensor input to calculate boost, how are you readings from the wideband comparing to your boost guage? On my boost guage I'm reading 10psi, but using the chart above I'm only getting like 8.4 psi? Which one is right? Mabye it's time to up the boost.

 

It has to do with your altitude. At my altitude (5000 ft), when the boost guage is reading 7psi my map is reading about 4.5psi. The lower your altitude, and the closer you are to sea level, the closer your boost guage will be to your map sensor.

 

So the map sensor is right? I would think since both are coming off of the same source then they should be the same? altitude would affect both of them though wouldn't it?