Trans cooler sizing

[TerryD]

Looking for some guide lines for sizing transmission coolers. Will be a 4L80E with a 2500 stall billet convertor, 505 cu in 640 hp, 3800 lbs, "spirited" street driven with some cone chasing from time to time.

Also looking for opinions on whether to run a cooler in conjunction with the cooler in the radiator. Personally I like the concept of this for bringing the trans fluid up to operating temp.