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#5---Rocker Arms & Geometry Whose fit best?

1/2/2016 David Hughes

And whose "real" Chrysler rockers do we see beautifully mounted atop Indy heads in photos 14 and 15 along with their "real" Chrysler rocker shaft hold-downs, one guess "Gold Race" breath! If you think that is good lookin' you ain't seen nothin' yet. Look at the beautiful rocker arm geometry in the bottom 2 photos, these are to die for. But wait, there's more: WARNING, DO NOT LOOK AT THESE PHOTOS IF YOU HAVE PRETTY ANODIZED ROCKERS. Photo 17 is similar to 16 as it shows the roller position on the stem tip with the valve on the seat. Note that the roller is just to the intake side of the center of the valve. Photo 14 "Real" rockers   Photo 15 Mouthwatering objects of desire. ; Photo 16 They're all so beautiful they just make you want to cry. Photo 17 Geometry never looked so good. In photo 18 the valve is at 0.400" lift and the roller is at the end of its travel outward, toward the exhaust side. From this point on any increase in lift will cause the roller to travel back toward the center the stem, photo 19 shows the roller at 0.750" lift which leaves the roller more centered on the stem when the spring pressure are the highest. Photo 20... the rest of the story.   Photo 18 Is the roller going to roll off of the tip of the valve? Quick! Look at Photo 19. Photo 19 Nope, everything is where it should be, oh ye of little faith. Photo 20 Do not drool on the keyboard, it makes the keys all sticky.   This geometry is not the same as the theory that says the roller should be at the center of the tip at mid-lift and continue on out over the stem, toward the exhaust side, as the lift increases. Our way, and many other very credible engine builders believe this too, is to reduce the length of the roll across the tip there by concentrating the force in the center of the valve stem reducing any side thrust of the stem against the guide. Click here to view our Rockers.  Small Block   Big Block