Engine/Transmission (1998.5 - 2002) What Comp Settings for various applications?

[BILLYGEE]

I'm curious as to what settings to use for daily driving, towing, etc. I know about fun setting(s) but normally I want best all around performance and mileage, etc. without burning things up. I've been searching and reading posts till I'm blue in the face and would appreciate some experienced input. I've only had the box for a couple of weeks(pump tapped) and last week I towed my boat w/box set at 5/2(probably not recommended), boat weighs about 2500# or more and I got 3 more mpg then I used to get w/o the box. If this continues on most normal settings I'm gonna be happier than the only rooster in the henhouse. How bout some feedback? Thank you. Bill

 

[Gary - K7GLD]

Comp settings are pretty tightly tied to other engine mods - the setting that works well in a towing situation on a stock truck will likely NOT work well on one with big injectors added, etc. - so direct setting comparisons might be unreliable.



I was able to use 5x5 towing 7% Sierra grades with our fiver - engine otherwise stock - but I seriously doubt that will still be the case (or even needed!) with the 1. 6 injectors, BHAF and 4 inch exhaust mods I recently added. I'll know more soon, after our first RV outing with the new BOMBS... Oo. Oo.

 

[Mad Bomber]

Comp is generaly set 1-3 for daily driver, This is also a good setting for towing too. Do you have bigger injectors? Keeping the comp at lower settings will help the VP 44 live longer.

 

[rweis]

I would be a little careful about the "new" sudden increase in mpg.



As I understand it, the computer mpg has a lot to do with the TPS (throttle position sensor). With the box on, it is feeding more fuel for a given pedal position. The mpg computer thinks the truck is stock and somehow it is getting way more mpg and reports it as so. Tain't necessarily so.



A true hand calculation of miles driven and galons used is about the only way to get accurate mpg as soon as the engine system is modified with anything to do with the fuel delivery system associated with the TPS (injectors, boxes). Even running a stock engine the mpg calculator is not real accurate.



Bob Weis

 

[Gary - K7GLD]

I would be a little careful about the "new" sudden increase in mpg.



As I understand it, the computer mpg has a lot to do with the TPS (throttle position sensor). With the box on, it is feeding more fuel for a given pedal position. The mpg computer thinks the truck is stock and somehow it is getting way more mpg and reports it as so. Tain't necessarily so.



A true hand calculation of miles driven and galons used is about the only way to get accurate mpg as soon as the engine system is modified with anything to do with the fuel delivery system associated with the TPS (injectors, boxes). Even running a stock engine the mpg calculator is not real accurate.



Bob Weis

Dern, Bob - ya mean I'm maybe NOT getting that 25. 6 MPG the overhead 'puter is reporting since the injector/exhaust upgrade? :-laf :-laf



Now ya got me wondering if the 200 degree drop in EGT is off as well!

 

[BILLYGEE]

Readings were hand calculated

The increased mileage figures were hand calculated... I keep accurate records and hand calculate every fillup. Have done this ever since I owned a set of wheels, bout 40+ years... Tells me a lot bout what's going on.

 

[R-N-R]

I tow on 2x2, run around on 3x3 and save 5x5 for the right time and place

As was mentioned, setting are very dependent on performance setup and driving style.

 

[Mad Bomber]

As was mentioned, setting are very dependent on performance setup and driving style.

And how big your shower heads are :-laf