e-cam with 1.7 RR's on a 331???

[HotRoddin]

Originally Posted by 83GTMUSTANG

Wanted To No The Difference, It Seems An X Cam Has .542 In. Lift Vs. An E Cam With 1.72 Rr's = .529 In. Of Lift,..........so How Is It The E Cam An 1.72 Will Break Springs An Bend Push Rods..............but I No Plenty Of People Running A X Cam Or Similar Cam And Never Had A Problem...........explain This Agian To Me ..........thanks

Look at it this way 83GTmustang... you get more lift from 1.7 ratio rockers because you are moving the pivot point of the rocker arm closer to the pushrod ... the change in leverage gives you more movement on the far end of the rocker from the same movement on the pushrod end ... but that same change in leverage (in this case negative leverage) means you have to push harder to get that valve spring to compress, so you're putting more pressure on the pushrod and the lifter and the cam lobe with the higher ratio rockers. That being said, unless you're running very high spring pressures, very high lift, and very high RPM's it usually isn't that big an issue, just be aware it will tend to bend pushrods and flatten cam lobes quicker, the higher the rocker ratio goes.

If you're going to do it, make sure the extra lift doesn't cause your valve springs to bottom out, and make sure your valve to piston clearance is adequate to handle the extra lift.

I hope that didn't confuse you even more

Rod