no need for hi dollar coolers , I `ve run regular aftermarket coolers with and without going thru the rad , and never had a heat related problem.
I run my ''hose '' that I bought from american hose supply, and barbed fittings thru the rad. , and then thru the cooler and back to the trans , it runs cooler than the engine does that way . Always be sure to insulate where its close to headers tho----
