[99cumminsman]

I have a 99 CTD 4x4 and had 2 questions.

1. I have a Hypertech Power Programmer III, it has 3 stages and I was curious as to which would give me the best MPG.

2. Do stacks or straight piping the exhaust increase your MPG.

Thanks for any input.

 

[mstew75]

I have a 99 CTD 4x4 and had 2 questions.

1. I have a Hypertech Power Programmer III, it has 3 stages and I was curious as to which would give me the best MPG.

2. Do stacks or straight piping the exhaust increase your MPG.

Thanks for any input.

I have a '99 cummins auto 4X4 with 4" turbo back muffler delete edge juice w/attitude and I am getting 19.6 on the 2nd setting, tow, at 60 extra HP. On the mileage setting I got 17.5, thats 40extra HP. I figure with a air intake and some new tires I could get over 20.

 

[Hypertech Support]

I have a 99 CTD 4x4 and had 2 questions.

1. I have a Hypertech Power Programmer III, it has 3 stages and I was curious as to which would give me the best MPG.

2. Do stacks or straight piping the exhaust increase your MPG.

Thanks for any input.

Unless towing heavy I'd think stage 1 or 2, but since you have all three why not test them all out?