08 n54 coupe twin snails ??

Ok so i have moded my car. And have beat many american cars even some vetts. My tranny is going out milage is 100362. I dont know what the tranny cost is should i go standard or should i slap a nice 408 stroker d-1 procharger 4l80e then go turbo what opinions do yall have i live in the border by the way roma tx..


Thanks cirio

08 n54 coupe twin snails ??