Our Oldsmobile pulley kits are made from 6061-T6 billet aluminum and machined in the USA. Oldsmobile used 3 different water pump lengths on their engines.   We have pulleys designed to work with both the 5.6" and 6.0" tall water pumps.

5.1" Tall - E-Body with A/C
5.6" Tall - All Others
6.0" Tall - A & E Body without A/C

We always recommend measuring your water pump before ordering.