Mike/Johan - my thoughts about neg. inj. slope and WOT/PE...

Post by **06MonteSS** » Wed Feb 28, 2007 2:32 pm

Ok, here's my thoughts and their basis - please let me know your input...

After installing my CAI, my car was lean - giving me +ltft's. This would mean that my car was also lean at WOT/PE, correct?

Since going negative on injector slope tells the ECM that the injectors are smaller and makes them spray MORE fuel (making it richer), I set my injector slope to -5% to bring the ltft's down and get them in line.

Now, since the injectors are spraying more fuel - making it more rich - wouldn't this also bring my WOT/PE back in line where it's supposed to be as well??

Since the WOT/PE table doesn't know about the injector change and the injectors are now spraying more fuel - making it more rich - this is eliminating the previously lean condition at cruise and WOT/PE, correct??

So now if I go positive in the WOT/PE ranges, wouldn't I be making it too rich?? and if I went negative (as instructed in the user manual) I would just be making it too lean again??

Thanks!

johan · Post by **johan** » Wed Feb 28, 2007 4:01 pm

You are right in theory, however a CAI does not cause a huge difference in WOT air/fuel generally so therefore we say to bring it back using the WOT PE.
Unless it is more of a ram air style cai this will apply.
But you are right in your line of thought.

Post by **06MonteSS** » Wed Feb 28, 2007 5:22 pm

ok, so if it doesn't make a big difference when at WOT/PE, then the injector slope change to -5% should be all I need to do then... since that will already be adding more fuel at WOT/PE, there there shouldn't really be a need to add additional fuel on top of that, right?

johan · Post by **johan** » Wed Feb 28, 2007 5:36 pm

Right, the difference is minute in this case.

Post by **06MonteSS** » Wed Feb 28, 2007 7:35 pm

cool, thanks man!!

I wish I was closer to you guys so I could bring my car right to the source to get tuned even better!!

I've done the whole CMR dealer lookup from your site, but I don't know who's good or not! Do you guys happen to know any personally or from high recommendations who is an excellent shop to deal with in my area?? My zip is 06798 - Woodbury, CT. I know, I know - "all of our CMR dealers can accomodate you, etc etc" ha ha ha ha ha... but having never been to any or had it done before, I'd like to know I'm going to a shop with an excellent reputation and that provides excellent results. I've heard some horror stories.... LOL

Thanks again!!
-Lew