I have a 1938 Oldsmobile business coupe it weighs around 3050 lbs with me in it it has a stock lq4 out of a 06 Chevy express with a 4l60e with up grades and I was told by the tourk converter shop with my motor and weight of the coupe the stall would be around 2200 to 2900 but I’m not sure it’s a gm310-Vj tourk converter the stall is 1800-2000 with the v6.
it also has the stock 04 truck harness dbw and psi conversions did my computer deleting vats and extra stuff not needed
and I asked and they turned off the neutral safety switch.
it have a b&m quick silver shifter in it also

i noticed today if I leave it in drive it will burn off the tires tell it shifts to second and if I put in 1st it won’t stay n first the rpms get to a certain rpm and it shifts into second with out me shifting and doesn’t burn out it seems dogish.




Any ideas why ?

thank you kelly