ok, so i did some logging today after extensive tuning. i've been fiddling around with the hptuners a good amount lately. So, i take a look at what i felt was my best launch from a stop/stall on the log, and i write down the time. 34.32.946 i then go grab my time slip from the last time i was at the track, and had zero traction. 15.01 at 92.5 mph so i then scrolll forward on the log, to where the truck hits 93 mph, and i write down the time. 34.46.946.

so..... 34.46.946-34.32.946=14.000

now.. my jaw drops.

i'm now in speed density, i've removed more torque management, i'm running more timing, and more fuel, i've done a ton more logs, and i totally got almost perfect traction ( just scrubbing a little, to help raise the rpms)

I have a stock stall, 3.42's and a g80 with 27" tires, true dual exhaust with stock manifolds, slp high flow cats, glasspack 2.5" mufflers, and 2.5" pipe all the way back. Upd intake, asp pulley, and lt1 fans.

is it just me, or was that an awsome time? is the timer correct or is it way off? i'm impressed either way, the truck feels the best it ever has.

I don't think the run was a fluke, all the other test runs i did, were real close.

 

are you serious? no one knows?

 

The timers acurate but you would have to be able to log mileage to know how long it takes to do a 1/4 mile. But yea you did lower your ET. I'm still running in SD mode. Just haven't had the time to calibrate the maf. I had it perfect until i guttted the cats and had to start over again tuning. This time it only took two logging to get it tuned. Now on to the maf calibrating.

 

93mph isn't enough to hit a 14.0 unless you had one crazy 60' LOL

Genberally speaking wqith an average 60' of 1.9 you would need about 96-97mph to hit a 14.0.. That's just an average for most cars.

I ran 14.29@97mph in the Z71 N/A on a 2.0 60' just for reference.

 

I've logged runs at the strip and it is very accurate. HOWEVER... you must have a good logged baseline run to compare with. For example, if you go to the strip and run a 14.5 at 93 and have the log you can later compare other logged runs back to that time and guage improvement as you will then know your time to a certain speed. You can guage whthter you got faster or not but still won't know exactly what you would run with the new mods. Granted you can predict future performance with a decent degree of accuracy if you stick with standard time/mph known data such as that mentioned by F8L above my post.

 

is who serious???


as for your numbers, i agree with F8L. to run a 14.0 @ 93 you'd have to have run a 1.8 or so 60' time. i don't see that happening on the street with your truck.

 

how do you take the speed density off? can allen do that?

 

Hey guys this is a cross thread! There seems to be a few of these showing up and they tend to be confusing. Here is the other thread in Tuning and Diagnostics .

 

Speed Density is a way to tune the PCM without using the MAF. You don't really take the speed density off per se. I'll let someone who really understands it tell you what it is and how you do it. If you do a search you will find some answers and a description of speed density tuning. Allen should be able to do it but would have to be tuning live on the street while logging the operating parameters from the PCM.

 

i get what you're all saying, and i feel a lil dumber now.... if my quarter mile time was gonna be 14 flat, i should be going faster, not still 93, unless i'm getting an awsome 60' time. Makes sense, so i'll really need a gtech to know, but if i look in the 97 mph area, and see 14.3 or so....i might be in that ballpark. thanks guys.