Idea for 2 bar MAP sensor hack

[turbo_bu]

Jim,

This is where you will have to log and play with it to figure out where things are at with your new MAP sensor and revised scalar / offset values. Basically, log it while running, but try to keep your foot out of the throttle. You will then be able to see what MAP value the PCM is reading, and the corresponding grams/cyl for a given condition. Use these values to modify your tune for VE and spark.

I tried to show what the "equivalent" MAP reading would be for a given set of scalar / offset values in the spreadsheet images in my first post. You can do the same so that you have an idea of how to translate your readings. There are also equations for calculating air flow based: this is an example using the 6L displacement.

Calc_MAF_SD(grams/sec) = VE(%) * [5.968(L) * 61.024 * RPM * MAP(kPa)] / [(IAT(C) + 273.15) * 212544]

Here's how to get from grams/sec to grams/cyl

CYLAIR(gram/cyl) = MAF (grams/sec) * 15 / RPM

[Jim Blackwood]

Yes, I've read quite a lot the last day or two and my conclusion is this: Idle is down in the .08 g/cyl corner and should vary much as the MAPvsRPM map does I think. WOT should be around .7 and anything above about .9 is probably going to be in boost. This is perfectly acceptable to me and I can work with it. I have loads of experience with timing maps and a pretty good idea of what they should look like. So onward I go.

I have not yet fired the car up with the new controller. Wanted to get as much of it set as I could first, and once I get through the timing maps I'll be just about there, so maybe another week or two. I can worry about logs and such after I've checked error codes, got an idle and such as that. Presently I suspect I may have to switch the wires on the cam pickup to get it to light off.

Jim