Bonneville Motor Prep: Rocker Box and Valve Springs

Hi All,
Ive returned from honestly “the best time in my life” out at Bonneville this year and and determined to get my BSA together to compete for next year. Been drafting a long post with lots of pictures from the trip but havent finished it yet. Stand Ready! Was out in the shop tonight working on the valve train of the race motor. Did a little lightening of the rocker arms, removing the casting flash and polishing out the stress risers. Pics tell the tail.

photo 2

Before and after

photo 3

I reduced the horizontal cross section and took some extra material off the outer most end at the valve.

My main goal with this is to lighten the valvetrain, this works by reducing the inertia of the rocker arms and helping prevent valve float,(we are running tight valve to piston clearance right?) I have already made some aluminum pushrods to replace the steel ones that came stock. Reducing the horizontal cross section does not effect the stiffness of the arm, the final shape is more oval, think of an I beam.

This brings us to the last piece of the puzzle, the valve springs. After much searching and spending a day on the phone and leafing through the comp cams catalog I settled on a ovate wire beehive spring. These represent the latest in spring tech only requiring a single spring as compared to the dual springs we are all used to. The wire and conical shape cancels out the bad vibes that will end my weekend, while allowing lower seat pressures.
If you think its wild that Comp would make springs for a 65 year old motor, your right, they don’t. The springs Im using are a combo of 4.6l 4 valve ford v8 springs, 5.7l dodge new Hemi Titanium retainers and valve locks for a small block chevy. I told you I spent the whole day in the catalog. The good news is these things are priced like your going to buy a whole set of 32 for that super sweet Ford 4.6 to go in your Mustang. Score for us 4 valvers.

I have not weighed this yet but the difference is considerable

I have not weighed this yet but the difference is considerable

Until next time
-DAN