Originally Posted by Cab_Burge
If I had to guess buy and sue one it would be the RPM up twocents


I would say it depends on the application and usage. shruggy
The standard Performer is rated at idle to 5500,
While the Performer RPM is 1500 to 6500.
The CH4B maybe in the middle. lot's of info on Google beer

www.tandmautomotive-omaha.com