So what exactly throws off AFR? If you command the tune to have 11.3-11.5 AFR from 5k up the computer will dump the right ammount of fuel to mix with the air keeping his AFR where it needs to be right? With piston protection active, will this just dump extra fuel and create rich conditions? I guess I don't really understand how a AFR could get into the danger zone on its own. Its all in the tune right? Maybe someone can explain this to me.

Sounds like it to me, anyways from 5k to redline.

 

Temp and altitude will both effect the AFR. When I tuned it we had all the fuel adders off (COT, piston protection, in open loop so the o2 sensors does poop). It was dialed in with in 1-2% error at 11.6 I think we left it at. I then put it back to closed loop so the o2 is back on and put piston protection at 5k I believe, so now above 5k it will be a tad richer than the 11.6 we commanded before.

He said he did not plan on getting a WB (then) so I didn't want to make it too lean because he has no way of monitoring it and I did not know how lean it would get in the winter time.

 

damn, this thread turned out better than I thought. Lots of good stuff in here. I had no idea that's what you had done...lol...........sad really since I was in the seat next to you and you explained most of this the day of

I guess I just needed it broken down into Barney mode.

 

Next time I will. At least when I learned I asked all kinds of questions. Get the parts you need and we can go to town.