I am just about out of warranty and plan on doing some mods to my 99L. I wanted to get a good baseline so I could see through the BS that gets spread around on parts.

The only things that I've done to my truck for this Dyno is to put a panel style K&N air filter in; the first time. The second run I had a mild street superchip (that promised 25 HP).

I just realized that I can't post a copy of they dynojet files... Well here is the results without the graph...

I did 6 runs, doing a 2nd gear pull (as I was told it gives the most accurate results)

(3rd run after engine was warm and fan was engaged)
Max HP 302.5 Max torque=402.1 (stock)

With mild street superchip (6 run of day, and cool down between stock run)
310.6 hp and 408.6 Torque.


As you can see I got 8 HP from the chip and 6lbs of torque. Not quit what they promised. It's interesting to see what you actually get when you stop 'bench racing' and do some real tests.

I've got the upper 2# pulley from downs and will probably put it on with the 90 MM MAF for my next test (with a chip reburn).... I'll update you all when I know.

One thing I did notice is that torque started at its highest at low RPM then dropped off whil HP built.

 

I'm surprised you were told to dyno in 2nd gear. Everyone else(my Corvette dyno operator too) said put it in Drive and bring it up to 3,100 rpms(so it won't downshift and then go to WOT.

Dan

 

We actually put it in 2nd to keep things similar to the next, rather then have the possibility for human error and different shift points (differnt chips later) from messing something up. We started in 2nd at a full stop, then WOT. Seemed to work.

The dyno tuner also told me he has had problems leaving it in drive for some of the L's. He believed the torque converter messes up an acurate reading of the torque curve. he claimed best results in 2nd for that too.

 

3rd gear pulls are a MUST. The tranny ratio is 1 to 1 and that is what you want for an accurate pull.

 

Only problem with 3rd is it will downshift into 2nd and 1st. You have to have it locked in one gear to go from 0-wot/top speed.

If it shifts you only see a part of your power curve. If you want to watch your curve and make sure you don't have flat spots 2nd is best that I've seen so far.

 

Well, it is known to downshift but you have to deal with it. your numbers would have been a bit better in 3rd....where the ratio is 1 to 1.

--wes

 

Do just like Dan said. Take it up to 3k in 3rd and then nail it. You will not downshift AND you'll get accurate numbers. You do not need at 0 to redline dyno numbers...

 

Don't listen to Jeff (although he's right for a change). 2nd gear will give you an easier mean to dyno test, but you can't say that you only got 8hp, when in fact that would have equated to about 15 if you would have done it in 3rd.

1:1 is the way to test.

BfB

 

Who the heck is this guy and what does he know?

 

Thats why you only got 310/406....

 

That's the first i've EVER heard of doing a dyno run in 2nd gear, even the Tuners use 3rd gear. As everyone has said, go back and do the runs in 3rd gear. Plus the power you gained from the chip sounds unusually low.?.?