So today we went to the track, it was horrible conditions with a 20-40mph headwind. But we had the wierdest thing happen, for some reason the truck ran richer on slicks that are 28.8 inches tall than on 22 inch wheels with 31.6 inch tall tires. It also ran extremely rich on 24.6 inch tall tires. I have a lm1 wideband but do not have the interface(i will be getting it next week) I WAS NOT watching the wideband during runs. BUT you can see on the narrowbands that the car was running richer, it was also running higher inj duty cycles, so it was definately rich. My question is Why would changing tires affect the AFR. All runs were on the same tune just changing the tire size. It was enough difference that the truck ran 11.94 on the 31.6 tires on 22's, 12.3 on the 28.8's and 12.4 on the 24.6's, and it was not running out of gear, all runs were finished in 3rd gear. the log with the tall tires and 22's was on the street also, not at the track. I did not log the 22's at the track because i gave up and just guesed they would be slower, but they are all on the same tune. run 1 is with 28.8 tires. run 4 is with the 24.6 tires. 2 out is with the 31.6 tires.
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