roller rockers

[JohnA]

I purchased a set of Scorpion bridged roller rockers for my 401 (3220502 heads) fitted with new Compcam lifters. Of course when I went to use my original 7.794" AMC pushrods, they were a 1/2" inch short. I made up a custom adjustable pushrod to determine the new rod length. I'm getting 8.250" which gives just slightly over a 1/2 turn of lifter preload. Has anyone installed non-adjustable Scorpion rockers and what pushrod length are you using?

[tufcj]

I moved this from the customer service forum.

Can't help you on the non-adjustable rockers. +.100 seems the norm for any adjustable, although every installation is different due to factory machining, valves, valve seat, head milling, block decking, etc. Just too many variables for a 1-size-fits-all.

Bob
tufcj

[fifesjeep]

I moved this from the customer service forum.

Can't help you on the non-adjustable rockers. +.100 seems the norm for any adjustable, although every installation is different due to factory machining, valves, valve seat, head milling, block decking, etc. Just too many variables for a 1-size-fits-all.

Bob
tufcj

X2

[ironman_gq]

do these require the rocker bosses to be machined for them to work right?

[JohnA]

No, they fit and bolt on nicely with the right geometry, just need longer pushrods. I have a picture of the engine 250kbs but can't figure out how to post it. Oh, by the way, you can't use your original valve covers, too low. You need approximately 3/8" more inner height.

[tufcj]

You need to use a photo hosting site like Photobucket (free) to post pics.

To change from bridged to individual rockers, they generally mill about .375" from pedestal, so .500" really doesn't sound that far off with no machining. If you still have the manifold off, the plunger in a hydraulic lifter should be compressed about .020" below the retaining clip.

Bob
tufcj

[tarior]

Doesn't sound outrageous to me. On the 360 I built years ago, I think I used 8.20" pushrods, and that was with adjustable rockers.