WOT launch

[matthewhagwood]

I have a 2011 Ram 5.9 Laramie with a Diablo Trinity programmer. I had a custom tune done by Hemifever and i love it. The only thing I'm not satisfied with is the launch from a dead stop. My question is what would my WOT fuel & WOT spark settings need to be to achieve a very responsive throttle at lower rpm's?

[mikel]

its not likely in the wot settings, Id contact the tuner and see if he can find any room for improvement.

[marku]

You could probley play with throttle boost a bit, but really if you have tall gears and a tall tire and a stock converter it's not going to launch hard

[matthewhagwood]

I believe i have 3.55 gears running 34"x12" Nitto Terra Grapplers. I increased the fuel to be a little richer and increased the spark a little and got an improvement, but i want to get the most i can without harming my truck. I know it can be done because ive seen other trucks, same year, that are mildly modified (intake & exhaust) with same tires that launched great.

[marku]

But a 34" tall tires and 3.55 with the 3.00 1st gear in the 545rfe or 645rfe is not going to launch hard at all. It all depends on the other trucks mods or gears as well too. They might have had 3.92 or 4.10 gears if they were a Ram. Or most trucks now like the Fords or GMC although they have 3.42-3.73 gears their first gear ratio in the trans are 4.00-4.05 which mult. the torque nicely.

[marku]

And you need log your data to see what your AFR and LT and ST knock is. Usually especially in my case I had to take timing away from the tune. On Shell 93 octane I was getting lots of ST knock. He pulled timing and reduced the knock senor sensitivity and it ran better. So adding timing isnt always the best thing to do unless you can see show much Long term or Short term knock your getting. The Hemi motors are very sensitive to knock

[bgramling24]

I believe i have 3.55 gears running 34"x12" Nitto Terra Grapplers. I increased the fuel to be a little richer and increased the spark a little and got an improvement, but i want to get the most i can without harming my truck. I know it can be done because ive seen other trucks, same year, that are mildly modified (intake & exhaust) with same tires that launched great.

If you want improved launch and acceleration, upgrade your rear differential to the 3.92 LSD or even up to the 4.10 gears. 3.55 does not have limited slip that I know of, and is only a 1 wheel wonder. My '12 Ram 1500 5.7L came factory with the 3.92 rear end, I have a CAI and a custom true dual exhaust, the Trinity T1000 and Hemifever tuning at the moment. I live on the coast, in FL ( @ sea level ) on a cooler winter night (36* F) last year, my regular cab short bed, 2wd, ran a consistent 0-60 time of 5 seconds flat. 1/4 mile times on long smooth asphalt were consistent as well with a best of 14.03 @101 mph. That was with Hemifever 93 octane tune as well.