At Eds In Joiliet Grumpy. We have both read that thw 4L808E is good for 800Hp & 800ft/lbs torque. Not sure if its true. I would upgrade to All parts that Sonnex & Trans Go has available to fit your budget. Red Alto Eagle frictions & Kolene Steels for sure. 300M input shaft. Heavy Duty Sprags. That eats up $800-900 cash right there likely. Then the Torque converter.....$1500-2000 or more.