ZR1 3 bar map setup on 03 tahoe 5.3l turbo with MAF.

[bradysrscr]

Hi Tuners, I'm having an issue with getting my scanner to show my 3 bar map. I have put the following in the map scale 305 and 10.33. When I go to log it shows that it is seeing map on the long term fuel trim, but seems to only show 45, 46, 47 kpa. nothing else. My tuner says there is something wrong and I think that the computer is just not programmed to display it properly. I have read to apply the 3 bar speed density file to my program but I am afraid to as I want to use the MAF for fine fuel control. The engine is a .30 over 5.3 with trick flow 305 heads, comp remote mount turbo cam. factory intake and 60lbs injectors for the 8.1 litre big block(496). I have the flowtech headers running into a 67 turbonetics turbo and will be using mostly for towing a bigger camper and car/ trailer. any help would be greatly appreciated. P.S. I verified that my original map was registering and showing scale perfectly so I know there is no problem with the computer.

[5FDP]

305 and 10.33 are the wrong settings.

The ZR1 MAP sensor has specific settings for the linear and offset.

They are 312.50 and -11.25. You must remove the 1 bar MAP channel and replace with the 2 or 3 BAR channel so you can read kpa over 105.

You need to apply the upgraded OS to properly tune the VE table for boost. I highly suggest you use the upgraded OS to make your life easier. Also the factory MAF sensor will not read a ton of airflow because of the small MAF housing.

Tuning in pure speed density can be just as accurate as a tuned setup for dynamic airflow if you know what you are doing.