#21  
Old 07-28-2020, 12:10 PM
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Roycroft Roycroft is offline
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Thanks, Jack. I would definitely have my machinist tap the stud bosses. I just saw your edit from an earlier post about burning oil holes in rockers, which I appreciate. I'm going to post my question about larger valves in the earlier heads over in the general street section to see if more people have input, but I'll start keeping a lookout for some 65 or 68 closed chamber heads.

  #22  
Old 07-31-2020, 02:37 AM
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Rocky 389 Rocky 389 is offline
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Back in the 70s I was running a '59, 389 in my 57 Chieftain, 2 door sedan and I pulled a rocker stud. I ended up with a kit that included a dedicated drill bit and an oversize stud. I used it and set the new stud with enclosed stud setter goop. Worked ok but I was always worried it would come loose again.
My latest build is a 57 block bored .125" to 370 cu in. I used 73-74 GTO [350] heads because they were like 96CCs, a good way to loose some compression from using old Jahns pop-up pistons. They also have hard valve seats, 7/16ths screw-in-studs [big block chevy pieces] and factory push rod guide plates. Had to grind a little from the bottoms of the valve retainers to clear the PC intake seals with a .90 valve lift Lunati cam. It all works great. I tapped and blocked the oil passage in the block deck...just a little insurance. I went with the reverse cooling block and front cover, made a pair of adapters under the '57 coolant elbows to direct coolant into the late heads. Mine uses a 59 manual bell housing, flywheel etc etc with a 11.75" clutch and a muncie M-21 4 speed. If your car only weighs 1800 lbs I wouldn't hesitate to use a saginaw 4 speed.
My stock '74 rockers oil just fine from the pushrods. I honestly don't remember what pushrods I used but I turned the engine by hand and watched the valves cycle....no weird angles or anything. I have about 10,000 miles on so far. I love it! Runs cool and strong.
Oh, and if you do score a 58-60 bell housing, be sure to get the manual trans starter too. It's shallower than the automatic starter. Mine is in my trusty old 34 ford coupe.
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  #23  
Old 07-31-2020, 01:21 PM
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Roycroft Roycroft is offline
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Thanks, Rocky. I saw your other posts on the water-neck adapters which will help if I go the route of later heads. I'm penciling out some solutions over the phone with another forum member familiar with the heads, and we might have something worked out to use solid screw-in studs, '65 rockers, and the longer '59 1.88/1.60 valves. I'd use my pushrod checker to make up any geometry issues and order whatever length hollow pushrods I'd need to get the rocker in the proper location on the valve stem. Of course, if I can find a set of usable '59 rockers, this is all a moot point but an interesting conversation (for me at least) regardless.

  #24  
Old 08-01-2020, 01:35 AM
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Jack Gifford Jack Gifford is offline
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It sounds like you're thinking of using '65 rockers on '59 heads. If that's true, then you've missed the point.

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  #25  
Old 08-01-2020, 02:16 PM
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Roycroft Roycroft is offline
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Quote:
Originally Posted by Jack Gifford View Post
It sounds like you're thinking of using '65 rockers on '59 heads. If that's true, then you've missed the point.
No, I haven't missed the point. I'm exploring whether adjusting the pushrod length might be all that is required to make up for any difference in the rocker arm design. I haven't been able to find exactly what the difference is in the rocker arms aside from that they look different and are a different part number. Have you by chance physically put a '65 rocker on an early head, set up the pushrod with an adjustable, and measured valve lift and stem wear pattern through a cycle? If you've done that and can confirm that the '65 rocker won't work no matter the pushrod length, that will save me time and money buying one rocker arm. If no one has done that, it's hard for me to rule out that adjusting the pushrod might resolve the difference.


Last edited by Roycroft; 08-01-2020 at 02:21 PM.
  #26  
Old 08-02-2020, 02:12 AM
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Jack Gifford Jack Gifford is offline
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Quote:
Originally Posted by Roycroft View Post
... can confirm that the '65 rocker won't workl [on a '59 head] no matter the pushrod length...
Yes, I can confirm that the '65 rocker won't work no matter the pushrod length.

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  #27  
Old 08-02-2020, 02:54 PM
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Roycroft Roycroft is offline
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Thanks for the confirmation, Jack.

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