I didn't want to risk overheating the new motor on the track so I replaced the wimpy stock radiator with a thick core Fluidyne:

Comparison pic of Fluidyne vs the stock DSM radiator:

The stock radiator is actually thinner than it looks. What you see in the pic is just the bracket. The core itself is even thinner.

Installation is a breeze since it's a direct bolt on. Just lift the radiator out of the car and remove the cooling fans and temp sensor:

I decided to be anal and filled the radiator with distilled water/coolant instead of regular tap water/coolant. Adding some Redline WaterWetter wouldn't hurt either. Also, supposedly mixing less coolant vs water gives better cooling so I mixed an approximately 40/60 ratio.

All done!