The stock turbo is pretty good being a 60/60/9cm but the tubine housing is tinny! So the best bet is to sell it and use that money to pay for a new one, that's what i did!!
What is the truck goona be mainly used for and what hp goal are ya lookin for?
You can also get the HTT in a 62/65/13ss and that will spool even faster and still keep things cool while towing, but drive pressures will be lower with the 71 turbine wheel over the 65 turbine wheel but if your just planning on adding a Smarty for some extra towing power then the 65 will be just fine! The 71 will be just fine as well and give you abit of growing room over the 65 wheel!!
Just my $.02