26 spline 833 horsepower

26 output is 66 and 67 with small block .....67 they introduced the 30 spline but it was wit big block only ......then in 68 they were all 30 spline untill ODs came then a lot of slanty ones were again 26 spline ...no problem they take the smaller 904 slip yoke .....for 500 horsepower ....i would totally go with a 727 .......even a 30 spline behind 500 horsepower is going to be problems .......the factory M-code cudas and darts in 1969 came with 727s only for that reason .....and even Mr. Norm Highly recommended the use of 727s behind high horsepower ...for the durability and tourque curve.

i have a 26 spline behind a Big block but a bone stock 383 ...so i can tell you they can handle that much .....but 450-500 horsepower ...your getting real brave to use it