Extender Chip & Tire Size

[tom h]

Does the Extender Chip's programming (and other popular chips , too) depend in any way on tire size?

When running 28" tall tires, engine RPMs will drop about 7-8% for the same road speed.

I'd guess at WOT it's irrelevant, and I'm concerned mostly with what effect there would be on normal driving around town.

Torque converter lock/unlock speeds seem one definite effect. Seems like lockup at 7-8% lower engine RPM will be even more annoying than it is now.

 

[TurboBob]

TCC, MPH, and chips

Unless you change the speedo gear in the trans, changing tire size
will have no effect on perceived TCC operation. The ECM will not be aware of the
change.

If the TCC is annoying, it can be programmed to suit your tastes. Extenders are typically
programmed without lockup in 3rd gear since the 3-4 shift is real clunky with the TCC on.

The 4th gear part throttle TCC is usually set to 44 mph, but is easily set to
whatever you require. Many guys with the multi-disk converters prefer a higher lock speed.

TB