HOW TO: Run MAP sensor only (v. closed loop)

[imdrax]

im trying to get this dialed in but cannot figure out how to do the pivot table, any help?

[prowakeskater]

PM me about the pivot table. I can walk you through it. I struggled with it for far too long, I dont wish that upon anyone lol

[ChrisCarey]

Originally Posted by Kooldino

PS - To make this work for open loop, use the same idea, except log your target AFR and your wideband. Then divide your target AFR by your wideband. Use that number as your data in the pivot table, which should be set up the same way.

Doh just saw this Quick question though, if I use the same pivot table and ftable whilst using your method above I get very small changes (2 units) for large discrepancies in AFR (9.99 vs 11.76). Should I be using a different formula like pivot table values (percentage difference from target and actual) multiplied by the current map which yields a 25 unit change?

[imdrax]

Originally Posted by ChrisCarey

Doh just saw this Quick question though, if I use the same pivot table and ftable whilst using your method above I get very small changes (2 units) for large discrepancies in AFR (9.99 vs 11.76). Should I be using a different formula like pivot table values (percentage difference from target and actual) multiplied by the current map which yields a 25 unit change?

I just put something together for this -> http://www.evoxforums.com/forums/sho...08&postcount=7

[jyamona]

Originally Posted by Murlo26

Yep, my car is setup to run MAF until 120 load then MAP above that. It works very very well.

Baka just set me up w/ something similar. MAF til 8psi~ish, MAP after. Works great

[Kooldino]

Originally Posted by ChrisCarey

Yea that's what I did (maxed all MAF values), idle and part throttle is good (except for some surge at idle and during decel) but I'm apprehensive about going into boost lol. How does one go about adjusting the MAP tables for boost?

Basically you do the same thing my spreadsheet does, except you want to log target AFR and wideband. Then instead of using fuel trims and adding them together for "totaltrim", just divide target afr by actual afr (or vice versa) to get the correction you need. Then use that as your multiplier on top of your current map.

In another thread somewhere, i made an earlier version of the spreadsheet that did just that. Probably could use an update, though.

That said, I'd advise setting your target AFR to 10.5 or so just to be safe.

[Kooldino]

Originally Posted by ChrisCarey

Hmm in that case couldn't you do a pivot table (RPM vs Boost) and use the difference in AFRMAP and wideband readings as the data for a similarly easy way to tweak the map scaling?

You could, I did that before, but the results were a little cleaner from using fuel trim info in the vac columns.

[Kooldino]

Originally Posted by ChrisCarey

Also, should I be resetting the trims/ECU after each change in scaling or no?

Only if it's close to +/- 12. When i zero out fuel trims, sometimes the cars won't like to idle until i drive them for a few minutes and it put some numbers in those fields.

[ChrisCarey]

Sounds good, thanks!

[imdrax]

So dino, how does doing it this way compare to doing it the way you posted by using trims?