You'll use HP Tuners a bunch more than you ever thought...

not because you have too...

because you want too.

 

I don't doubt that one bit. I will definitely be purchasing shortly. Both my daughters have birthdays this month and my girlfriend is the beginning of next month so I'm gonna be strapped for cash for a bit.

 

I have a test spot for seeing if mods do anything because how it feels has never been consistent enough. Too many times I've though my car was faster after I made it louder but it wasn't.

That being said when I bought this truck I found a spot to test and see.

After I did headers the truck picked up absolutely nothing. Then I got the tune checked and corrected and it picked up 3mph. And you could feel quite a bit of difference.
Not sure why but with my Camaro (2000) I could feel the headers without tuning, and not much of change with the tune, the truck was the total opposite.

 

The accuracy of that first statement is too tough to handle. LOL

I wish I had a good spot that was relatively easy to get to and knew I wouldn't be bothered often.

Its impossible for me to say one way or the other with mine since I did the headers and manifold/TB all together. It surely felt like it moved faster and had more low end grunt, but the exhaust note was changed significantly from the headers. I'm sure that the tune wouldn't be adjusted much, if at all, by the manifold and tb because the MAF should account for the increased airflow... right? But I'm sure that timing and fuel could surely be adjusted with the increased volume of air in, and with the help of the headers, out of the combustion chamber.

I definitely need to have the tune adjusted. It smells like its really rich at idle, I know eliminating the cats will make it smell more, but even in my cammed 99 without cats it wasn't this bad.

 

Actually it will self adjust, but only so much, for all driving OTHER THAN wide open throttle. At wide open it goes into open loop (unless things have changed) which is where it runs on a set program only, which will be the tune it had previous to mods.

And the self adjusting is very narrow, it adjusts up or down a small amount from programmed parameters.

My test spot is from a stop sign, to a yield sign about 1000 feet out, going up an entrance ramp to the highway. Your test spot can be anywhere, you're looking for something that you can keep consistent and measure time to see what actually happens when you test something out. I just check MPH, and I use my speedometer. I'm not getting too scientific with it.