That’s a Power glide input, with Th400 splines , and I would not run one of those behind a Pro Mod motor either , but if you will look close you will see that the oil hole is part of the reason they break, I'm also guessing that’s a Valasco shaft , the new Margian shaft with smaller oiling holes will stand up to a lot more . Ive broke a few of thewm also . that Why I run a Bruno Lenco .
This is not about gas or diesel , but sleddie is a sled puller , and will never understand drag racing , or the parts we use , his kind are trying to catch up with me , its about weight , weight , and calculated risk for more efficient and lighter parts. But when he starts bad mouthing one of the pillars of drag racing , about something he is totally ignorant about , I just have to put him is his place , dragging something heavy around in the dirt. This entire hullabaloo about the diesel being the king of torque is just a bunch of crap, the math will set you free. Torque is torque, and parts don’t care what the motor making it is burning. If I put twice the first gear in my 358 small block truck motor it will put out twice the torque , and more then the same hp Cummins motor to the u joint
Example
Keating 1000 hp truck at the 4500 + rpms he launches makes a peak of 1167 foot pounds of torque just say he has a 2. 50 first gear , that would be 2900 to the U joint
Pro Stock car, 1380 hp @ 8400 equals 862 foot pounds of torque with a 3. 30 first gear for a total of 2847 to the joint
Now a Pro Mod 2500 hp at 6800 rpms peak of 1930 and a 2. 50 first gear for a total at the u joint of 4800 foot pounds of torque . now you work with the math .