How are pulleys measured?? I have a 97 Bonne SSEi, just threw a Conn rod????? All stock 55k, go figure????? Must be a fluke! Anyways, I picked up a L67 out of a 01' Regal with 25k. While into the swap I noticed that the pulley sizes were different??? These are my findings: 97' outside rim=4 1/8", outside belt grove=3 3/4", inside belt grove=3 5/8".----------------------- 01' outside rim=3 5/8", outside belt grove=3 3/8", inside belt grove=3 1/4". There seems to be a difference in pulley sizes by aprox. 3/8"????? Both pulleys are black and look to be stock??? What does everyone think about this???? What about belt size??? If a stock auto store belt fits is it a standard stock pulley always?? Also what is the stock idler pulley size could that have been changed to(assuming a stock belt fits????) Very confused now as I was about to order a 3.4" pulley this week before installing engine. Thanks for all your input!!

One other thing---97' pulley is tapered from the rim inward to the center hole and has the numbers 86016 on it.
The 01 pulley is flat on the outside from the rim to the center hole and has no identification at all on it. ????????? Confused??

The '97 pulley is a stock 3.8 pulley. The '01, since it is flat, is a Pulley Boys pulley, probably a 3.4", possibly a 3.25 but I'm not sure.

Shawn

threw a rod?

Has this every happened to any other L67s here?

Not here, but many on Club GP have, and/or popped some pistons... Most of the time it'* due to bad timing from a computer and/or heavy Kr.

I would double check your fuel system, to make sure you don't throw another one when this motor goes in.