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Cliff your thoughts on roller rockers?

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quadrajam:
Slipper tip.  Part #  SUM-G6801. about $75.00 . Long slot grooved balls 3/8 stud.
Set of 16.

The ball grooves dont go all the way down to the hole although some oil could
possibly drain into the slots. I noticed when priming my engine that oil pooled in the ball
area on down to the rocker tips.  No problems so far @ ~5000 miles.

QJ

Mudsport96:
Awesome. I will look into those, I don't know how accurate my logic is on the subject. But I do know the faster ramp flat tappet cams have issues. So, maybe you can speed up valve lift some with higher ratio rockers. Maybe I'll get a set for just in case scenario.

77cruiser:
So far my Scorpions are holding up fine, but anything can & will happen sometimes.

Cliff Ruggles:
Grooved rocker balls are a HORRIBLE invention.  They give up bearing surface area and allow oil to drain down the studs instead of "pooling".

I found this out decades ago after watching them in action on a running SBC engine with the valve covers removed. 

The aftermarket roller tipped steel rockers also have a very POOR fit to the rocker balls and "grind" themselves into a better fit creating a butt-load of heat and putting a good bit of metal into your assembly. 

I can't remember removing a set of Comp roller tip rockers that weren't blue or even black and heavily worn where they balls ride in them.  They are pretty strong and don't fail, so most folks using them don't even know this is happening.

The other problem aftermarket roller rockers bring to the equation is weight.  Anytime you add weight above the cam lobes it REQUIRES more valve spring pressure to keep things in check. 

So keep that in mind when you buy cam "kits" with HUGE heavy retainers, locks, springs and then add heavy rocker arms to that equation. 

The problems with controlling valve action are further compounded by using cams with "aggressive" lobe profiles.  These "new" cam offerings often reduce seat timing, then get the valves up much quicker and set them down faster as well.  NONE of that is a good thing when it comes to having a stable valve train.

About the only cam designer that paid attention to all that was Harold with his Ultradyne cams.  Although they never really got off the ground Harold sold his lobe profiles to Lunati and pretty sure Bullet Cams. 

I'll add here that reducing seat timing then shoving the valves open faster to increase .050" and .200" numbers does NOT mean your engine will make more power.  Time off the seat trumps all that so a slightly longer duration cam, even with slower ramps and less lift can and will make as much as or more power than the "whiz-bang" lobes cam companies are promoting these days.

I am probably the only one who has actually back to back tested that deal and found that due to the lifter diameter flat camshafts just don't do all the great things they tell us when you buy into that technology. 

You also have to factor in the increases in dynamic compression and pulling peak VE down in the RPM range.  This fact can quickly make a relatively "low" compression engine not liking pump fuel much and pinging on it. 

Despite the proverbial "brick wall" of 9.5 to 1 for pump gas you just can't make big power at low compression ratios even with fancy cams in these engines.  Compression is your friend with these things and you can make a LOT more power with higher compression, longer seat timing and wider LSA's plus enjoy smoother idle quality and improved street manners at the same time.......I'll sit down now.....

Mudsport96:
No need to worry about taking a seat Cliff. I asked because I look for your opinion. Following advice I have gotten from here, I have helped people with problems that they had been fighting. I've talked others down from the "I need roller rockers" ledge, as I feel quality is not as good as I needs to be. Like I said before, the only reason I have them is they were already on the car. And they seem to be quality pieces from Harland, so they stay for now.

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