Turbo 350 Trans Shift/Slip issues
Hi, I'm new here and will hopefully stick around if this deal on a 70 Monte Carlo goes through. That being said, I wen't to drive the car in question 350 engine and 350 trans and what I had happening was this:
The owner said the car was once an automatic converted to manual shift via a solenoid that selects the gears so I would go from L1 to L2 to D as you would from 1st 2nd to 3rd.
So I head out for a test drive and it starts not shifting into a lower gear when I go to L2. I learn this is because my revs aren't high enough so I correct that and it shifts OKAY. I say it like that because almost every time I shifted into 2nd(L2) it would jerk very hard chirp the tires and 3rd(D) would as well just no tire chirping. Well as I start driving on the highway everything is going good until I give it more than a half throttle and it starts spitting smoke/backfiring when I let off the gas. Then it just cuts out on me all and all and I have to wait for the owner to come with a new battery because apparently the alt was shot. So after we get the new battery I start following him home.
On the way home I notice if I give it more than half gas in 3rd(D) it shifts into a higher gear and gets stuck there until I shift down into 2nd(L2) and then back into third. Which is annoying because I have to slow down to about 30 to shift back into 2nd without im sure locking up the rear wheels.
Anyways I like the car and the engine runs strong as ever minus the smoke and the backfire which I'm not sure can happen because of a bad battery but was gone after the new one was put in. So I would like to know what this could possibly be given the description. I know the description was not perfect and I know relatively little about these Chevy's since I normally have Mopars(please don't shoot me). So I thought I would ask some of you as you would know better than I. Thank you for your time.