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Discussion Starter · #1 · (Edited)
Fellow 68 Camaro owner Mark got his dad's Z-28 years back. Has been sporting a 383/ 5 speed since I've known him. Typical "465 horse crate 383" here. Some 5000 miles back, valvetrain noise. BLOOD PERF in Auburn, WA discovered bad #1 intake pushrod, upper tip was worn off. They replaced both #1 rocker arms and pushrods.
Now #1 intake rocker cup and the upper pushrod tip are worn again, look chewed-upon.

383
Patriot Heads 64cc 2.05/1.60 1.46 dual springs and dampener
full stainless roller rockers 1.6
chrome moly pushrods
Howards 224/230* .501/.509" 110* HR (no exact match, seems like this
Howards Cams Hydraulic Roller Camshafts 180245-10
unknown to me or the owner what lifters, Howard or the stock Chevy stuff. Dogbones and spider system are present.

Melling 10550 HV oil pump
speed pro Hyper E flattops, says 10.4:1 CR on spec sheet.

other interesting bits:
some coating has worn from the front cam bearing though no galling
cam looks fine
some outward splaying of the rockers, suppose this is due to wider valve guide spacing

will check pushrod length for wear pattern
possible valve springs are bad or are at an unhappy set-up
HOWARD tech guy said valve float rpm would be difficult to calculate...
owner says he has seen oil pump from all the pushrods....but cannot rule out lifter unhappiness

oil starvation seems most likely followed by geometry or possibly a combination of the two.
says 20 psi at hot idle going to 65 psi
owner is likely to pull the heads for servicing
(edit: NOT the parts I'd use mind you except the Howards cam, good stuff there)

Thoughts?
Will get some pics up
 

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Discussion Starter · #2 ·
Pics of the damaged goods. 5000 miles
 

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Are those some kind of Chinesium Ebay rockers? Wonder if the cup was bad from the start?
 

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Discussion Starter · #4 ·
true, one possibility....the originals died and one replacement, believe COMP, is now dead. These two new ones are different than the surviving 14 originals
 

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Pushrods sure do look spread out more than normal.

What kind of pushrods? Imported pushrods?

Rocker tips centered up on the valve stem?

Just a wild guess, but I wonder if the angle of the pushrod is putting the oil feed hole too far off center, and it's not allowing good oil flow in the cup of the rocker? Or maybe pushing more against the side of the cup?

Interesting..
 
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