The difference is about .035" between those part numbers. The first number, MPR103B is approx. 8.685" long and the other, MPR308, is approx. 8.650".
The MPR103B is a G.M. pushrod while the MPR308 is listed for a Ford application.
Both have oil holes for the rockers so the application won't really matter as long as the lengths work!
The numbers you have are 5/16" pushrods, the G.M.'s factory truck "tall-deck's" were 3/8". The early 427" G.M. "tall-deck" intakes average 8.680", but as I stated, they are the 3/8" diameters. They are interchangeable, but you must use the corresponding guide plates.
Thanks, Gary in N.Y.
P.S. This info is taken from the Melling catalog as it was installed in our computer.
The MPR103B is a G.M. pushrod while the MPR308 is listed for a Ford application.
Both have oil holes for the rockers so the application won't really matter as long as the lengths work!
The numbers you have are 5/16" pushrods, the G.M.'s factory truck "tall-deck's" were 3/8". The early 427" G.M. "tall-deck" intakes average 8.680", but as I stated, they are the 3/8" diameters. They are interchangeable, but you must use the corresponding guide plates.
Thanks, Gary in N.Y.
P.S. This info is taken from the Melling catalog as it was installed in our computer.
