#21  
Old 06-27-2021, 09:39 PM
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Originally Posted by pastry_chef View Post
With the photos above, I'd agree.
I think it was post 7.. full sweep of 9.2 . Getting closer than I'd like to exhaust side of valve tip.
I'm curious how 9.15 full sweep might look compared.

I do like where the 9.2 begins
Thanks Pastry, I just edited my post above (#19) while you were posting a reply, just incase you missed it

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  #22  
Old 06-27-2021, 09:43 PM
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Quote:
Originally Posted by pastry_chef View Post
With the photos above, I'd agree.
I think it was post 7.. full sweep of 9.2 . Getting closer than I'd like to exhaust side of valve tip.
I'm curious how 9.15 full sweep might look compared.

I do like where the 9.2 begins
We will do the full sweep with the 9.150" and report back in just a few minutes

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  #23  
Old 06-27-2021, 10:07 PM
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Ok, here is full sweep with the 9.150" pushrod and 1 full turn of the engine. Lifter at zero lash.
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  #24  
Old 06-27-2021, 10:09 PM
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Post 23 looks like about as good as you'll get.

Edit.. maybe 9.2 is better,, looks more narrow IMO.


Last edited by pastry_chef; 06-27-2021 at 10:14 PM.
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  #25  
Old 06-27-2021, 10:19 PM
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Quote:
Originally Posted by pastry_chef View Post
Post 23 looks like about as good as you'll get.

Edit.. maybe 9.2 is better,, looks more narrow IMO.
Here is the witness marks, one on the base circle, one at 2/3 lift, both with the lifter at Zero Lash, at 9.150".
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  #26  
Old 06-27-2021, 10:22 PM
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I was thinking by the time a person preloads the lifter .050" or so, the 9.200" may end up being the best, although the witness mark on the 9.150 is pretty centered, but that is WITHOUT any lifter preload too. I am by far not an expert though, that's why I need help LOL

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  #27  
Old 06-28-2021, 07:43 AM
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Are your factory rockers new or used and can you post up a pic of the contact face on them.
Would be interested to see the diff in radius of the contact area on the stamped rocker, Vs the radius of a common roller tip rocker

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  #28  
Old 06-28-2021, 08:55 AM
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Originally Posted by 455-4+1 View Post
Are your factory rockers new or used and can you post up a pic of the contact face on them.
Would be interested to see the diff in radius of the contact area on the stamped rocker, Vs the radius of a common roller tip rocker
We are checking with the factory rockers, but they are in excellent condition. We will be using New Comp Cams replacement 1251-16 though, which are exact specification as the stock rocker that we are measuring with. We are still awaiting delivery of the new rockers, so we are measuring with the stock rocker, but since they are identical specs, there should be no difference between the two as far as pushrod length. I don't have any pictures of the stamped rocker contact face at this time, but I can get a picture this evening.

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  #29  
Old 06-28-2021, 11:44 AM
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I would wait till new rockers are in hand the new face at the tip might make pushrod checking easier due to a new surface

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  #30  
Old 06-28-2021, 12:16 PM
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Quote:
Originally Posted by TransAm 474 View Post
We are still awaiting delivery of the new rockers, so we are measuring with the stock rocker, but since they are identical specs, there should be no difference between the two as far as pushrod length.
Different rockers locate their pushrod seat differently. Aftermarket rocker ratios will differ slightly, stamped steel ratio will differ more.

I'd also wait for the new rockers.

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  #31  
Old 06-28-2021, 12:49 PM
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Quote:
Originally Posted by pastry_chef View Post
Different rockers locate their pushrod seat differently. Aftermarket rocker ratios will differ slightly, stamped steel ratio will differ more.

I'd also wait for the new rockers.
^^^ x2 on this ^^^

ALL rocker ratios vary slightly from manufacturer to manufacturer and style to style.

Since you are going to all this trouble to get an optimum-length pushrod, make certain that it is optimum with your NEW rockers.

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  #32  
Old 06-28-2021, 01:29 PM
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Thanks guys!, as far as what I have measured so far(with the current stock rockers), what length do you guys favor the most? I was leaning towards the 9.200" by the time a person figures in .050" or so of lifter Preload. We will definitely check it with the new rockers when we get them.

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  #33  
Old 06-28-2021, 03:04 PM
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I vote for the 9.200”.

While you have some time it would be interesting to cycle thru all of those stock rockers on that one valve just to see how much the ratio veries.

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  #34  
Old 07-03-2021, 03:29 PM
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Ok guys, we got the new rockers today, and remeasured using the adjustable pushrod at 9.200". To me, the witness marks look even better with the new rockers, and I think the 9.200" is the winner. One mark is on the basecircle, the other is at 2/3 lift, both with the lifter at ZERO lash. By the time a person figures in .050" of lash, I think the 9.200" will be as close as we can get. We also measured with it at 9.150" appreas to be a little too short.
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  #35  
Old 07-03-2021, 03:54 PM
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Looks good.

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  #36  
Old 07-03-2021, 03:57 PM
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Looks good.
Thanks! I'm gonna go ahead and place my order at Butlers for the 9.200" .116" wall. I appreciate all of your help very much.

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