I have a Honda S2000 that I have just fitted a Rotrex Supercharger, intercooler, 750 injectors, AEM V2 EMS with an AEM UEGO gauge

I have just added an omnipower 4 bar map sensor as the stock map sensor maxes out

I've added the new cal for the sensor from http://www.omnipowerusa.com/calibrations.doc

I've then set my Load breakpoints (-/+0.1) to be the same as they were previously (with 2 missed off the bottom and 2 new breakpoints at the top to cover the extra boost not being read by the original MAP sensor.

I've then copied and pasted the fuel and ignition maps for the all load points that are still the same into the new map and then kinda made up some numbers by copying the old highest load figures for the 2 new load breakpoints in preparation for a tuning session.

However, fitted the new sensor, uploaded the new map and the car is massively too rich. I had to take out about 50% fuel at idle to get an AFR of about 13.5 .... car is warm, checked the enrich map to make sure that is not having any evvect, turned off O2 feedback to prevent that making any changes. As soon as I blip the throttle AFR drops to 10 (lowest on scale) and stalls. If I take 50% fuel out I can just about blip the throttle.

I guess I've done something wrong .... Do I have to use all the points on the new MAP sensor, is that my problem. ie. the sensor goes to 44psi but my highest breakpoint it 13psi.

I've checked to make sure that Micro sec/bit is set correctly and it is the same on both maps.

AEM cal for honda map sensor : http://dl.dropbox.com/u/16722287/s20..._map.01v22.cal
AEM cal for omni map sensor : http://dl.dropbox.com/u/16722287/s20..._map.01v22.cal

Any ideas?

cheers
Robert

 

You may have better luck in the FI forum. Make sure your conversions are correct. I honestly think it's a combination of the wider scale sensor and the maps. I can't give you any specifics, but that's your problem.

Your dividing the same 0-5v signal from the old 10psi sensor over a 58psi sensors output. Your original scale values will be way at the bottom quarter of the sensors range. You have to shift all of your MAP values to match that.

 

you couldn't just change the map sensor info in the old map to the parameters specified by omni?

 

I don't think so as it doesn't rescale the fuel map

 

Swapping from stock to a 4bar will require a retune.

 

Thanks, but I don't really understand why. My map is good up to 10 psi so putting the correct values in for the same loads *should* work. It's going to be a lot of work to start from scratch.

 

Easiest fix is to put the old MAP sensor back in and take it to a tuner

 

SOLVED

needed correct cal for map sensor. Data from omni was not working, using AEM wizard worked fine

 

So, to state again, you just needed the correct map sensor info plugged in?

 

Yes, that is what i had done to start with but the sensor info provided by omni was not correct! I used the wizard and therefore the sensor info from AEM