How is "M4" better than tow/haul or just normal mode?

 

M4 is Manual shift 4th gear, you should always use tow/haul when pulling a load. It helps protect your tranny and gives you the right gear for the speed and the load your hauling, not to mention it helps you gear down so its not all on your brakes to stop the heavy load. Hope that helps.

 

Hah - just noticed your sig! WOW - a IV GTO, NICE! Through the years I've owned several dozen Pontiacs, including a handful of 455HO cars and one SD T/A, but never a IV car - congrats! I'd love to see your collection someday!

Listen - I drove 120 miles each way from Sugar Land to Victoria for Patrick G to tune my Denali - from San Antonio you can't be too much farther than that. And Kurt's place is actually on the NW side of Victoria . . worth the trip IMO. FYI - Pat does take Saturday and Sunday tuning appointments. He tuned mine on Sunday Jan 9.

If not, Allen Nelson has a good rep dyno tuning our trucks, and he's in San Antonio. http://nelsonperformance.com/

Also, Nelson is holding his 3rd annual GM truck drag event at SAR on Feb 26. Ive already registered . . . http://www.ls1truckraceday.com/ Maybe I'll see you there?

 

It's not, just decided to make my runs in M4. I highly doubt that it makes ANY difference at all, though.

Tow/Haul mode upshifts are firmer, but the shifts are at a LOWER RPM at WOT than non-Tow/Haul shifts. Once again, I did NOT make my passes with Tow/Haul mode selected.

 

Mark - have you run your truck down the 1/4 yet?

I'd also sure like to hear from Area47 to see if he has any ideas about my miserable day at the track.

 

I was mad as chit the other day, my best run was 13.70@102.8mph w a 2.19 60' (+900 DA)...Come to find out I was pulling 5* of timing out the hole on that run, that's the only reason I hooked. The other runs my i couldn't stick...1-2 upshift was a big prob for traction as well...only records were hot laps. I coudn't stick when the motor was cool...

My best run before headers was 14.19@99mph w/5k miles and 85* temps...no traction issues...

 

it seems everyone is set on dyno numbers. sure it's all glitz and glamor when you make big numbers. when it really comes down to it. track times show it all.

your short times need some work, but that is also knowing when the breaking point of traction is for your truck. this in itself takes a lot of track passes. i think i have 50 or so passes on mine so far. i got the launch down to a science in my truck.

something else too. i slowed down my shifts. if you're spinning, you're losing valuable time.

DA and air quality plays hell with these trucks.

i don't use manual mode, aside from the burn out. after that. it gets shoved back in drive. shift trigger is set at 6100 in 1 through 4.

 

I always tune my vehicles to run fastest in Drive. Manual mode is not going to give you the fastest ET. Also keep in mind, the humidity was 94% when you ran. Not good for best ET.

 

Thanks for stopping by, I was hoping you would.

I really, honestly don't believe that I'm getting ANY tire slip on launch - except that awful first pass. And if it's chirping the tires on the 1-2 upshift, I can't hear or feel it.

What RPM do you launch at? I was launching just above idle - like 800-1000 RPM, trying to flash the converter as high as I could. Also, are you running the OEM torque conveter and rear gear?

DA was great at HRP (now re-named "Royal Purple Raceway") yesterday - 138'.

Next time I go to the track - Feb 26 @ SAR - I'm gonna run in D.

Also, do you switch off traction control and stability control for your runs?

Thanks in advance!

 

Thanks for chiming in, Patrick. Will do on Drive range for my runs from now on.

Humidity was indeed high, in fact the only reason I made no more runs was that the rains came at about 7:15 and they shut the track down for the night.

Everyone, please understand that I'm not at all unhappy with Patrick's tune. Quite the contrary - I'd do it again in a heartbeat! And my next vehicle will go to Patrick for his tuning.

Something weird is going on - it's making my truck feel sluggish at the top of 2nd gear and making the 2-3 upshift quite violent. We'll get it firgured out.