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I posted a prior thread about options for the 289 in my '65. After a lot of good advice, I went with my original idea of keeping the stock heads and having them ported/cleaned up. I just got them back (they look great to me), and I'm getting ready to start reassembly now. Trying to make sure everything gets done right, I started doing some reading on rockers and how to set lash, adjust valves, etc. and learned about the different requirements for roller vs stock rockers. The rockers that were on the car are Comp 1442-16, which depending on what you read, are either "roller rockers" or "roller tip" rockers. The only literature from Comp I could find mentions that these rockers should only be used on heads that either have guide slots or guide rails installed. Am I correct in my understanding that my '65 289 heads are early enough that they do have guide slots (the slot in front of the rocker stud) and that these are the correct rockers for my motor? It's not about saving or spending money - it's about getting it right. I have no need to upgrade these rockers if they work, I just want to verify that they're the correct ones before reinstalling them. My understanding is that '66 and on heads no longer have the guide slots and would need to use a different, rail-type rocker. Do I have this all right?

I've attached pics of the rockers and the heads. I also included some pics of the port job that was done, just to see what everyone else thinks. I am more than happy with his work, but this is my first time doing all this and I probably wouldn't know if it was subpar or not. I got what I thought was a very fair deal - cleaning/disassembly of heads, port-matched intake and exhaust ports on heads and the new intake/exhaust manifolds, cleaned/tested/back cut valves, new upgraded valve stem seals, and reassembly for $650.

As always, thanks for the help and input. Hope you enjoy the pics.
 

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You have the pushrod guide slots in your '65 heads so no additional aligning devices such as pushrod guide plates or rail style rockers are needed. These guide slots are not in the rocker arms- they are the slotted holes in the head casting where the pushrods pass through the head. On '66 and later engines those holes were round and were much larger than the pushrods so some other device was needed to keep the tips of the rocker arms on the valve stems. Ford's solution was to add rails to the sides of the rocker arm tip to keep the rocker aligned.

You have roller tip rockers. A full roller rocker would have a trunion and needle rollers where the main body pivots on the stud. Your rockers still use the original factory style ball there.
The porting job looks good to me but I'm no expert on porting.


Here is a photo of the rail vs non-rail rockers.
 

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They look good! And, you have slotted pushrod holes so you're good to go. What I would do, just to make sure (your machinist may have already done so) is run a cleanout tap down all the threaded holes and blow them out and, when installing the rocker arms, setting them up so that at 1/2 total lift the rocker arm centerline is exactly perpendicular to the rocker stud.
 

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And make sure that you use the correct push rods. I think they have to be of the hardened variety, but ask someone with more info than me.
 

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...when installing the rocker arms, setting them up so that at 1/2 total lift the rocker arm centerline is exactly perpendicular to the rocker stud.
The point of that is to insure that the travel of the rocker arm tip is centered on the valve stem, correct? If so, the typical process for determining pushrod length should be all that is needed.

I am not sure one can accurately determine the centerline of the rocker, measure a perfect 90 degree angle and then get the valve to stay at 50% lift with hydraulic lifters. While this might be possible with great effort with solid lifters, I would see some bleed down of hydraulic lifters throwing the geometry off.

Is there a reference for a procedure to do what you describe?
 

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And make sure that you use the correct push rods. I think they have to be of the hardened variety, but ask someone with more info than me.
Assuming the heads were simply removed from the block, the existing pushrods are of the correct material. The pushrods are likely the correct length unless the head surface was milled significantly. I did not have to change pushrod length when changing from stock rockers to the roller tip Cranes...but it is good practice to check.
 

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The point of that is to insure that the travel of the rocker arm tip is centered on the valve stem, correct? If so, the typical process for determining pushrod length should be all that is needed.

I am not sure one can accurately determine the centerline of the rocker, measure a perfect 90 degree angle and then get the valve to stay at 50% lift with hydraulic lifters. While this might be possible with great effort with solid lifters, I would see some bleed down of hydraulic lifters throwing the geometry off.

Is there a reference for a procedure to do what you describe?
https://www.dragzine.com/tech-stories/engine/engine-tech-understanding-valvetrain-geometry-and-getting-it-right/


 

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^^^ That's all fine, but overkill for most street engines. We are talking stock heads (outside of some porting) and basically stock rockers here . The heads still have press in studs, so it's not likely to see over 6,000 rpm. The OP will be fine using the Sharpie method to confirm pushrod length. He can even use an existing pushrod to check the sweep. Only if the pattern is off centered does he need to buy an adjustable pushrod to determine proper length so that proper length pushrods can be ordered.

This video shows how the blue tool is used.

<iframe width="961" height="721" src="https://www.youtube.com/embed/UBO-Mgp0Og8" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>

Here is a nice video showing the process but I do not see how it would work with a ball type rocker:

<iframe width="1280" height="720" src="https://www.youtube.com/embed/o5is9BsH5OU" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>
 

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Discussion Starter #10
Thanks all for the replies. I was planning on reusing the pushrods that came with the rockers, as the valves are stock size and the cam is a pretty mild one w/ sub-.500 lift. But, I'll definitely make sure to check everything as I reassemble!
 
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