Roller Rocker Side Clearance

[Ricks70Duster340]

I am using Harland Sharp roller rockers on my 440. The instructions say to have a side clearance per cylinder from between .008 to .012. I recently took my engine apart to deal with other issues and am now reassembling things. I noticed some of the rockers and .047 spacers show interference wear on the sides. I called Harland Sharp and talked to the tech who said I could use their .031 spacers to make more room.

Having the minimum recommended clearance was obviously not enough. What are your experiences for the proper clearance? As I recall the OE rockers had quite a bit of clearance.

 

[GTX JOHN]

I run 8 to 12 on my race cars that never see the
street.

However on my street / strip cars I run 25 to 30.

On my street only stuff, I do not run aluminum rockers.

Jesus is Lord!

 

[fishmens67]

I set rocker side clearance at .015, most times I have to take a little off the shaft stand retainers to get it perfect.
Perfect valve tip alignment with perfect side clearance

 

[mopowers]

I set my PRW stainless rockers at 0.015" per pair. I start at one end and use a feeler gauge as a spacer while snugging up the next hold down, then move on to the next one and so on.

 

[Bewy]

With roller rockers, you should be centering the roller tip on the valve stem. Stock rockers have a veeeeery wide footprint & have plenty of leeway. Not so with a narrow roller tip. Get the tip centered, THEN use shims to position the rocker. You do not need a lot of side clearance, 0.005" each side is fine. Too much side clearance, & the tip can move off centre.

 

[Ricks70Duster340]

With roller rockers, you should be centering the roller tip on the valve stem. Stock rockers have a veeeeery wide footprint & have plenty of leeway. Not so with a narrow roller tip. Get the tip centered, THEN use shims to position the rocker. You do not need a lot of side clearance, 0.005" each side is fine. Too much side clearance, & the tip can move off centre.

The issue is with the wear I am seeing on the sides of the rockers and the shims even though the clearance is on the low end of the spec at .008.

 

[Ricks70Duster340]

The issue is with the wear I am seeing on the sides of the rockers and the shims even though the clearance is on the low end of the spec at .008.

View attachment 1716308563

Got an email back from the tech at Harland Sharp. He recommends .015-.018 clearance cold that I could achieve by mixing/matching the thin spacers to achieve. I understand 440 Source recommends .015-.030 for a similar rocker.