canucklehead

Greetings olds fans.
Is there a cerpentine pulley swap for a 425 cid motor?I have a 425 and 455 blocks but no brackets for the front of the motor.Can anybody help?
Thanks

Oldsguy

I am not aware of a serpentine set up available for the 435 nor the 455. I saw something over at ROP I think for the 350. Personally, I would not do it. What is the reason you want to? There was a thread that mentioned that and I think it was C.J, or maybe Norm that mentioned if you have a belt failure with a serpentine set up, it all goes. With the old style set up, at least you might still have water pump operation if you have only one belt go on you.

joe_padavano

There are no TRUE serpentine belt setups for any Olds motor since nobody makes a reverse rotation water pump. The only Olds-style reverse rotation water pump ever made was used on the V6 diesel in the early 1980s. This WILL bolt to a V8 (hint, hint).

The alleged "serpentine" belt systems sold by March and others simply use a multi-rib flat belt and a boatload of idlers to properly tension the belt on the water pump. In my opinion this is an overly complex and expensive solution to the question no one asked.

If you have your heart set on one, all Olds big blocks are the same externally, so a 455 system should fit on a 425 or 400. I don't know if these systems include accessory brackets or not. If not, the early brackets are different from the 68-up brackets so the system may not work anyway unless you change over.