It just seems to me that with mods...chip, filter, pulley, and shift kit that I can feel the truck fall off the power band. There is so much pulling power down low in the rpm range I just wonder if you would lose any performance in the 1/4 mile. It could help us keep the bottom ends in our trucks. How about it, anyone know the answer to this? If you did not lose over a tenth or two I might have mine just shift at 5000! Sal, JL?

Jerry

 

Good question, I was thinking of lowering mine to 5200 or 5300.

 

I can tell you that I tried a program for JL one time and the shift points had got messed up. The truck shifted at like 5300 (May have been lower I dont remember) and it fell flat on its face... I didnt like that one at all. If I remember right DL tried it with me, we ran each other and both noticed it!!

 

Back in 99, I spent an entire day at the track testing different shift points. Shifting in the 5400-5500 range was optimum at the time. Dropping down to 4900-5000 slowed the truck down, even though I thought the truck might ET better staying in an rpm where ther is more torque, but it did not happen that way. That's why we test!! Or course now there are so many different mods, that some trucks require different shift points, but I still like 5400-5500 for the trucks with the normal bolt ons.

 

I like mine shifting right there to. Feels really good and its just before the peak part starts to drop off!!!

 

It would diffentely put less stress on the rods. I think it would not be too much slower, especially if you had more gear. Like 3.73 or 4.11's. The L's strong point is torque, so....Send it in for a re-burn and tell us.

 

I played with shift points last year and had one that shifed at 5200 instead of 5500. It was a slow dogggggggggg. Sent it back fast for a reburn. 5500 with strong shifts for me.
To stay in the max torque range you have to shift above the max torque range so when the engine falls back it will still be in the max torque range.
noelvm

 

On a road course, I'd like it to shift at 5000 rpm. Useable torque is more useful over time (1 - 2 hours for instance). Plus, reducing stress on the drivetrain gives me the opportunity to go back the next time!

Spike

 

Peak torque comes at 3500rpms and peak HP comes in at 4900rpms everytime on my truck.I was looking through my last few dyno runs and from 4900 to 5400rpms my truck lost between 16 to 23HP on average so there is a quick dropoff.My trucks shifts currently at 5400 and when i watch it fall back after the shift it is around 3800rpms which is still in a good power zone but not at the premium spot of 3400-3500 which would be interesting to find out with a modded truck!

Matt

 

How accurate are our tachs? Mine looks like it shifts about 5600 or maybe the tach swings a little past the actual rpm at WOT. I do not know.

 

Thats exactly what I'm gonna do when I get a chance. Once side of my chip is gonna be street use and the other is gonna have 5000rpm shift points for Auto-X and Road Courses.

 

The tach is the most accurate factory gauge you have, it reads off of the coil on one of the plugs, I think. The speedo is pretty good, the rest are about crap, I think.

G