Shift Programming question

Turbo6inKY

Short Guy
TurboBuick.Com Supporter!
Joined
Jun 18, 2001
Ok, I need a thing answered.

Shift programming for a TH200-4R with CK's parts and valvebody mods, PTC 3100 stall non-lockup 10" converter. 3.73 rear gears and 25.7" tall tires.

1 on the selector holds it in first. No problem
D on the selector gives you 1-3.
OD gives you 1-4.
My question is about position 2.
2. It doesn't lock you in second. And it'll downshift to first.

But going through data from my event today, it is upshifting, at WOT, into second at just 23 mph before the tires have even grabbed. Is 2 supposed to short shift?
Here's the chart, you can see the RPM dip from the 1-2 shift, and the shift happens at just 4475rpm.
Then again, I just went through a log from the NCM road course, and my 3-4 shift happens at 5075rpm at 80mph.

This engine is a 4.1 roller conversion with a 212/212 Comp cam in it. It's supposed to make power to 5500, so I think I'm shifting myself short.

Do I need to lighten up the governor assembly?

Video of the run below the screen cap. Unprepped asphalt parking lot launch.

1531685502657.png


 
Where does it shift 1-2 if you put it D?

Good question. Oddly enough, I've not had the chance to punch it from a dig in D. I've always autocrossed in 2, and none of my road course starts were WOT through 1 and 2.

It's raining here today, maybe tomorrow I can find a quiet road with no po-po.
 
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