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What is it that makes you feel it is way off??

Don't go by where it is contactng the valve stem tip....centered on the stem contact is not of primary concern. The often repeated secondhand and magazine published "adjust pushrod length to obtain centered contact" was never correct.....it just got repeated so often everyone believes it is correct.

Typical mid-lift method with the most frequently/commonly used SBC parts will result in a roller tip contact point that is typically outboard of center, toward the exhaust side.
Pushrod length will also be between +.100" and +.200" longer than stock in most cases for the set-up you have.

As far as contact point on the valve tip, divide the stem into 4 equal width sections ( about .080" width per section....you don't want the valve to get much outside the 3/4 line, or .080" from the edge of the valve stem tip.....maybe .060" from the edge at the smallest.

A cylinder head with +.100" longer valves puts the rocker tip farther out on the stem....this is because the rocker stud and the valve tip get closer togther as each is made longer.....they are on convergent angles.
 

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Discussion Starter #382
Ok. Then I guess I'm good. I'll just run through it once more to be certain. I'll post my steps to make sure I did it correctly. I bought a 12 inch caliper to measure and I'll post that info this evening.

Just to make sure, this is the correct number to use for my calculations right?
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Hard to say by the pics, but based on Eric's comments it looks like the roller is too far outboard. That's better than too far inboard since it will roll inboard as it opens the valve. The valve lift is the cam lift (0.350") multiplied by the rocker arm ratio (1.5) = 0.525". Did you roll the motor around to check for piston to valve clearance? I'd guess you will be fine, but with 0.525" lift, I would definitely make sure both intake and exhaust valves are clear of the pistons. I attached a document that is helpful.
hrdp-1303-04-checking-piston-to-valve-clearance-comp-xr276hr10-rocker-ratio-with-piston-graph.jpg
 

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Yes, the .525" valve lift figure is what you use for the calculations.

If you feel like you are too far outboard on the stem, you can cheat slightly shortedr on the pushrods by .050" and not hurt geometry too much.

With most available shelf stock pushrods coming in .050" increments, any length you measure that is short of a full .050" increment you can round down to help move the rocker tip inboard a touch....say you measure out a 7.987" length, round down to a 7.950" pushrods rather than up to the numerically closer 8.000" rod.

Don't forget allowance or compensation for the hydraulic preload in the lifter plunger setting after you measure your checking pushrod.
 

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Discussion Starter #385
So this is with zero lash and no preload.
411167


Here's the clearance clay. I forgot to cut it to measure though.
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[I would figure that since you want to move the contact pint inboard a little that instead of adding .021-.042" more for lifter preload(1/2 to 1 full turn) and getting a 7.550" pushrod, to just not add any and order a 7.500" pushrod, which would pull the contact point inboard once it is adjusted ready to run with lifter preload.
Sometimes you have to make minor compromises in ideal geometry to accomodate available parts....being .050" shorter than ideal on the pushrod is still a lot better than it would have been with a much shorter stock 7.300" roller cam pushrod or if you had just ofhand added +.100" to that stock length to "match" the valves in the heads.

If you were chasing the ideal geometry and just would accept nothing less, Crower sells a "backset" stainless rocker arm with the stud hole in the pivot offset .050" to move the entire rocker body back toward the intake manifold and placing the roller tip closer to center on the valve.
$$$ though. Beyond that would be a full-tilt shaft rocker set-up.
Straub Technologies may have a Crane Gold rocker that also has been re-designed pivot length to fit mid-lift and also be on center with the valve on heads with +.100" longer valves. I know that have them for the BBC, maybe they also do for the SBC. You could check with them if you feel the need.

Looks to me like you have a mile of clearance....if you want to double check the entire valve pocket I typically fill both intake and exhaust valve reliefs with clay just slightly higher than flush, wet them with a wipe of oil, and roll it through a couple revolutions. You can then section it with a razor blade in 2 or 3 places in each relief and compare with a dial caliper for thickness.
You may find the exhaust doesn't even touch the clay., and the intake will be the only one leaving an impression.
 

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Discussion Starter #387
[I would figure that since you want to move the contact pint inboard a little that instead of adding .021-.042" more for lifter preload(1/2 to 1 full turn) and getting a 7.550" pushrod, to just not add any and order a 7.500" pushrod, which would pull the contact point inboard once it is adjusted ready to run with lifter preload.
Sometimes you have to make minor compromises in ideal geometry to accomodate available parts....being .050" shorter than ideal on the pushrod is still a lot better than it would have been with a much shorter stock 7.300" roller cam pushrod or if you had just ofhand added +.100" to that stock length to "match" the valves in the heads.

If you were chasing the ideal geometry and just would accept nothing less, Crower sells a "backset" stainless rocker arm with the stud hole in the pivot offset .050" to move the entire rocker body back toward the intake manifold and placing the roller tip closer to center on the valve.
$$$ though. Beyond that would be a full-tilt shaft rocker set-up.
Straub Technologies may have a Crane Gold rocker that also has been re-designed pivot length to fit mid-lift and also be on center with the valve on heads with +.100" longer valves. I know that have them for the BBC, maybe they also do for the SBC. You could check with them if you feel the need.

Looks to me like you have a mile of clearance....if you want to double check the entire valve pocket I typically fill both intake and exhaust valve reliefs with clay just slightly higher than flush, wet them with a wipe of oil, and roll it through a couple revolutions. You can then section it with a razor blade in 2 or 3 places in each relief and compare with a dial caliper for thickness.
You may find the exhaust doesn't even touch the clay., and the intake will be the only one leaving an impression.
I'm not looking for prefect geometry. I just want a happy motor. I forgot to mention that I put a washer under the rocker stud just to simulate more threads. I can't see this being an issue but I wanted to run it by ya'll first.

Also in the picture you can kinda see where the roller is hitting the valve stem. Does this look ok? I was only fixated on it being in the center because two videos i watched on YouTube showed them lining it up in the better and calling it good.
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I like those guide plates! Good idea. That's more toward the center of the valve than it looked in the previous pic.
 

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Discussion Starter #389
I like those guide plates! Good idea. That's more toward the center of the valve than it looked in the previous pic.
Yes. Once i saw where the roller is in contact with the valve stem I felt much better.
 
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