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Discussion Starter #1
Ok, we tore my motor down to the block today, and put the 65 289 "k" Code heads on. However, when i went to switch the rocker arms over from the 351 head, I had a thought. ARE THEY THE SAME? The valve stem sticks up a lot further on the 351 heads than the 289 heads. The rocker arms are the RAIL type. So the stem of the 289 head did not come up far enough to hit the arm. But the rails were on the spring, and held the rocker straight. So i thought they were wrong. At auto zone, they said "as I tighten down the rocker arm, the spring will compress and the stem will stick up further, and contack the rocker arm" This sounded logical tonite, so i will try it tomorrow morning. Is this correct? Will these rocker arms work with my 289 heads? Thanks Adam
 

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What Auto Zone? So I can have that dumb ass fired!

Your valves and the rockers are wrong. If the rocker is hitting the retainer, and NOT the valve tip it will unseat the locks, and viola, MR valve drops into the combustion chamber.

If the valve tip and the rocker tip are not touching, and the rocker is touching the retainer..... THAT IS WRONG.
 

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If you have Chevy valves in the 289 heads, you might need a different length pushrod to make it work. Good luck. Tom
 

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If you are going to use stock rockers, then you are going to need to use non-rail rockers (circa 63-66) on those heads if they still have the stock short stem valves.

buddy rawls
 

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You can't run the rail rocker arms on heads w/ pushrod guides or the pushrod hole slots that those heads should have. You'll need to get non-rail rockers somewhere.

Yes, get that autozone dude fired for everyone's sake.:evil:
 

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Auto Zoners Rule !!!!!

Ya , these guys @ Auto Zone are sure the smart ones !!!:rolleyes: I hate going in there....I just got in to a argument with them about a distutor for a carb'ed roller cam motor.They kept giving me a dist. for a auto (Cast iron gear)
And after I got the right one , I BET that they Still don't know what I was talking about !!!:mad: As far as the rocker go , Some one said that the rockers are needed for the heads that have the push rod guides cast in the heads ,that sounds right to me....
Aren't the HI-PO heads the ones that have the guides cast in the heads ? Or did all the early heads have them ???:confused:
 

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Yes, the early heads came w/ the pushrod guides already cast in. Ford supposedly changed around the end of '65 to the rail rockers. My '66 has rail rockers and it was built in late '66 but I don't think I've seen heads w/ the cast in pushrod guides but I know they exist.

I'm pretty sure all the K code heads came w/ the cast in pushrod guides.
 

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Early 289 heads had a narrow slot that acted as a guide for the pushrod. Later 289 heads had a larger round hole, and used the rail type rocker to keep every thing lined up. Page 119 in the 2002 FRPP catalog has some drawings showing the differences in in the rocker systems.
 

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pushrod slots are not really part of the equation. plain and simple if the valve stem does not protude high enough above the retainer, you cant use a rail type rocker.

If you have to go to a non-rail style rocker then you will have to have some method to align and maintain the rocker position.

But the first order of business, is to get the rocker arm up above the retainer, in the full range of movement

Buddy Rawls
 

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Rocker arms & retainers.....

I just had a problem with some Crane retainers ,that if you used the "stock" locks (Other then the fact that the installed height of the spring wasn't right...) The rocker arm would bottom out and hit the retainer ,which would have caused some high RPM fire works....I found out that the crane retainers (Intake only) use a
Crane spec lock , that pulls the retainer down more so the valve tip isn't so close to the retainer(and set the right installed spring height,too) to allow the tip of the rocker arm to to bottom againsed it....Is this what your talking about???:confused:
 

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Discussion Starter #11 (Edited)
Ok guys, here's what i did. My dad, ASE Master tech of 41 years, and ex ford mechanic for a long time, said for now it would be ok to grind enough off the rail until the valve stem actually touched the rocker arm. So that is what i did. It starts and runs fine for now. I knew what i was talking about at auto zone, and every one kept saying ford never made a non-rail rocker. And we're think this dumb 17 year old knows nothing. BUT I WAS RIGHT. Which leads me to my next post. I am driving with a ticking sound from the engine. My dad said it's probably a lose valve, but has not heard it himselve, only what i have described. it goes along with enigne RPM, and get's worse the higher you rev it. it's coming from the passenger side (1234) bank. The motor makes TONS of power now with the heads, but that noise makes me nervous, so i haven't gotten on it hard yet, not over 2500,my dad is going to check it out tomorrow. Sooo....Should I go to a parts yard, and tell them to get me 16 NON RAIL pushrods? OR are mine fine with the modification? Thanks Adam
 

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New rockers & fulcroms are not expensive. Find a "good" parts source & buy new correct arms.
 
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