New slick tires - slower ET... TCM tune?

[Benltr]

Hi guys,

want some help from people that has been to the track with their street tires and than had some slick.

Did you change your tcm tune ?

My tcm tune is working perfectly with stock size tire (265/70/17). I gained maybe 0,15 ET and 1,5 mph just by raising shift point VS stock tcm tune.

But then i put some 28" cheater slick and i'm slower in ET and MPH vs my street tires. The 60' is better with the slick too...

I'm kinda wondering that the smaller tires make the truck shift too high in rpm.

Slick should help me with 120 pounds less of rotational mass and better traction... Also i can boost more of the line...

I ran a consistant 0,1 behind my street tire and approx 1-1,5 mph less too. It wasnt really the temperature since it was colder, the pressure was about the same and the humidity was a little high but not to make that difference.

Any experience from you guys that had a great street tire setup and than changed to slick? Did you made any changes?

Thanks

 

[Harbin_22]

With my 28" drag radials on a single cp3, same day. I ran 7.4x's all day long. Last pass, put the BMF/proxes on and went 7.5x. The only real difference was the 60' was .1 slower. Is you converter locking the same? Thinking it could be taking longer, since you are leaving harder maybe?

 

[Chevy1925]

Ill bet your trans didnt like the fact it had the shifts coming up faster so it may have hung a hair longer. I went from 37s to 265s one night to see what it would do. It took .10 off my et but my trans was hangin shifts and acted like i put it in relearn.

 

[Benltr]

Tested it last weekend.

Wasnt the tcm tune.

I ordered a BT Lock up. We'll see this weekend if it was the converter locking later with smaller tires.