The Ford Barn - View Single Post - Insufficient Hardness of New Lifters & Cams

ms fowler · 01-01-2025, 06:38 AM

I too have heard these horror stories--new cams/ lifters wiped out while being run-in on the dyno. I have heard several explanations--the switch to roller cams and lifters by oem has reduced the demand for flat lifters. That reduced demand has made the businesses that provide that service less profitable and driven many completely out of business.
All that makes sense to me.
My question is --How much "credit" for cam/lifter failures goes to the increased spring rates to get ever higher RPM?
Are we safer when we keep spring rates at, or close to stock oem?

01-01-2025, 06:38 AM	#3
ms fowler Senior Member Join Date: Mar 2022 Posts: 175	Re: Insufficient Hardness of New Lifters & Cams I too have heard these horror stories--new cams/ lifters wiped out while being run-in on the dyno. I have heard several explanations--the switch to roller cams and lifters by oem has reduced the demand for flat lifters. That reduced demand has made the businesses that provide that service less profitable and driven many completely out of business. All that makes sense to me. My question is --How much "credit" for cam/lifter failures goes to the increased spring rates to get ever higher RPM? Are we safer when we keep spring rates at, or close to stock oem?