At engine idle it will up shift from 12-15 mph
moderat throttle opening will upshift from 27-44 mph
At WOT (full throttle) it will upshift from 44-49 mph
That is all with stock 3.38 axle ration & tires that are the same rolling circunfrence as stock.


BC
1960 Chevy C10 driver 261 T5 4.10 dana 44 power loc
1949 GMC 250 project in waiting
1960 C60 pasture art
Retired GM dealer tech. 1980 - 2022