I am looking for suggestions for a diablo chip for my 1999 F150 4.2L automatic. Mods are K&N cold air intake, JBA shorty headers, & Gibson cat back single exhaust. Most of my driving is normal around town driving, about 5K mi./yr. The mods were installed to increase performance while towing. Most of the time I would be using the stock mode. I'd like suggestions for my other tune to compliment the mods during towing.

 

As far as the Diablo chip goes, if you want improved towing, you'll see a pretty big torque gain from installing the chip. The Diablo chip is switchable from stock to performance. The performance setting gets better with better fuel. using 93 octane instead of 87 octane.

 

The 4.2 has an enormous amount of untapped potential and it really wakes up with a chip.