I will contact the owner to see what on the tranny he blew besides the converter, I do know in fact that he bought new discs for the tranny on a Hyundai Dealer since this cars are Grey Market, Tranny Is Same as Santa Fe (old Model) ...
waplus
projectfreetv.onl

 

510nm is the max torque on that tranny but there are people with modded boxes who are pushing 600nm

 

Can be more, requires welding, clutch pack modding & remapping. 4 planet, Wavetrac & hardenned diff tube for big kw.
Your Airtrek non acd tc is Not as strong as an Evo non acd tc. Your rear is 3.312 & poorly mounted.
So beware how much kw you go for

 

how much torque can the transmission handle after all of those mods?

 

Not sure, don't know when it would slip
I run high pres with my 2.4lr