Cam Lobe Centers

[Ed Valvo]

I see posts of cam lobe centers ranging from 109-113. What are the advantages or disadvantages of let's say going from a 109 to a 113 and vice versa? Assuming duration and lift were the same on both cams.... I'm interested in which could make more power and which would have an effect on emmisions.

 

[S10xGN]

Wider lobe centers decrease overlap which increases idle vacuum and smooths the idle at the expense of mid and top end. Lower emissions = wider lobe centers, more power = narrower lobe centers. The trick is finding a lobe center that will suit your combination while giving you a good compromise on both of these qualities.