rocker arm and valves differences

[TobyB]

here is one with the hairline cracks

Crap, Pat, I have never seen one like that.

I wouldn't use it.

As to 11000 rpm.... that's a faster piston speed than F1 runs, currently...

it certainly wouldn't be viable for a long straight, and given

how much breathing an M10 head can do before

you open the intake and exhaust runners into water, I can't see

that you'd make a lot more power up there.

I also want to hear it!!!

t

[AceAndrew]

But another consideration is the pad's length and position relative the rocker safts. For example, I think the IE HD rocker are a good value if they're any stronger than stock but I noticed that their pads are .050" or so closer to the rocker shaft than stock which allows their leading edges to nose into a Schrick 316's lobes at a harsh angle right around 50% lift.

]

Looks like those IE HD rockers are shot-peened as well.

[PatAllen]

here is one with the hairline cracks

Crap, Pat, I have never seen one like that.

I wouldn't use it.

believe me it was on a working motor...almost all of them are like that, when i look at them with a magnifier. I did try to break on and it truly seems to be only surface, the pad is not cracked thru.

I even heated one glow red and it still holds. I will not use theses for sure...

[Harv]

I think the most important thing is that the curvature of the rocker pads line up perfectly in sideview so that the valves experience the same acceleration and motion. (either as they did before when replacing all 8, or as each other if replacing singles)

But another consideration is the pad's length and position relative the rocker safts. For example, I think the IE HD rocker are a good value if they're any stronger than stock but I noticed that their pads are .050" or so closer to the rocker shaft than stock which allows their leading edges to nose into a Schrick 316's lobes at a harsh angle right around 50% lift.

Maybe its no big deal?, obviously they wouldn't have that issue on all cams, but tellyawhat this set is spankin new and for sale if anyone would like to try.

[/img]

That's interesting. However it looks like it's on the back side of the lobe. Is that correct? I hear what your saying but I might be tempted to think it's not a big deal (or as a big deal) since it's on the valve closing side of the profile.

John

[Deilke53]

quote]

That's interesting. However it looks like it's on the back side of the lobe. Is that correct? I hear what your saying but I might be tempted to think it's not a big deal (or as a big deal) since it's on the valve closing side of the profile.

John

Nope, unfortunately that's the frontside of an intake lobe.

I agree dragging the pad noses down the backside of the Ex lobes doesn't seem as risky since without that sharp leading edge it wouldn't be shearing off the oil plus the spring pressure would be on the decline anyway.

[Harv]

Hmm...

Now that I think of it there might not be any difference to the amount of contact. Remember they are in a sense two circles rubbing on each other and the area of contact is small. The ramp angle does look a little steep though.

Never mind... I looked at that picture again.

John