I plan have a transmission swap to an automatic with overdrive done sometime next month.It is a 1968 with a 502 HP 502 bigblock in with a Turbo 400 in it.A guy is telling to have a 4L60E installed and it will hold up.Luckily my friend Douglass told me that the 4L60E will not hold up and break suggesting I have the 4L80E installed instead.I am not doing it,my friend Douglass is doing it since I am not mechanically inclined and he is.I drive it heavily with my lead foot and on the street.Inputs are very welcomed

 

I'd go with a well built 700R4 or a well built 200R. No matter what automatic you install you need to make sure it's not in stock format behind a 502, or it will break if you put your foot into it a lot.
Whichever you choose be sure it's been properly built with a good clutch pack, and stage 2 or 3 shift kit, and the proper torque converter for your engine.

 

I plan on doing burnouts too.Talked to a transmission shop that my mechanic Gerald knows also.Owner of this transmission talked me into a 4L80E too and he has one the shelf already for installation for $2,000.00.He would sell it to me for $1,500.00 giving me a price break.It has been rebuilt with heavy duty clutches,a heavy duty torque converter and parts.

 

If you can get your hands on a 4L80E and make it work, then go with that.
Strength wise, the 700R4 is equivalent to the TH350, and the 4L80E is equivalent to the TH400.

 

Thanks for the advice.I bought the 4L80E today with the computer and wiring harness needed and seen the paperwork on all the parts that were used during the rebuild.Goes in next week and have the turbo 400 sold already.Sold the turbo 400 to my huband Robby's friend AJ.