Any issues with early CI heads?

Invectivus

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I have an early, unserialized CI head. I don’t recall issues specific to the early prod runs, though I know some heads have had pushrod geometry issues depending on the run.

Anyone know something I don’t?
 
I haven't seated it on a block yet, So I have no idea of the alignment ATM. But yeah, that was the post I was thinking of, where they sleeved the pushrod hole. that's a thing I hope I don't run into. I need some work on it, I just want to verify any issues to remediate all at once rather than make several trips to the shop.
 
I bought a cylinder head back in 2008. Been On car for about 10k.. No issues. You must have had one of the very first cylinder heads. I do not recall anything about pushrod geometry issues.. I do know classic inlines Valves, that they sold with head, were not long enough, causing you to use 1.5 rockers or buy longer valves to accomadate different rockers.. Also the single springs that came with heads were not good, and came with no spring seats...
 
I have a CI aluminum head # 035. I ran it 10 minutes on my 200 build before the lobes on the cam rounded off and the engine quit running. My fault, trying to break in a new Clay Smith cam and lifters with dual valve springs. I bought a 65 long block with good compression, adjustable rockers. I put the block on an engine test stand, connected all the systems and tested them, everything is functional. There is 120 lbs compression in each cylinder, 30 psi oil pressue at ifle, 50 psi at 250o rpms. No smoke no knocks or clatters. Now I have pulled the stock head and am preparing to install the aluminum head, 4bbl intake and headers. I am keeping the stock, all ready broke in cam snd lifters. What fo you all think of this plan?
 

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For informational purposes, may not apply to you.. The old stock cam is broken in, and each lifter mated to each lobe, if they are not kept in the same order, you run the risk of lobe failure. That is because of old machining equipment was not that accurate and the bore of the lifters will be angled or spaced different and the cam also.
 
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For informational purposes, may not apply to you.. The old stock cam is broken in, and each lifter mated to each lobe, if they are not kept in the same order, you run the risk of lobe failure. That is because of old machining equipment was not that accurate and the bore of the lifters will be angled or spaced different and the cam also.
Thank you. I will keep tht lifters and pushrods in order.
 
252/256 112 LC I have a new Clay Smith cam with 110 LC. A bit afraid to use it. I’m too small to fail.
I think in this day and age that a camshaft needs to be broken in with OEM springs and then swapped to the heavier springs after breaking it in. Also make sure that the springs are of a recommended spring rate and pressure from the manufacturer or less.

I broke my Clay Smith camshaft in with the OEM springs and will be installing the heavier ones later this year.

On a related note, last year I had a chat with the guy at Clay Smith who designed the H-6474-0-B camshaft and he said he designed it for the Classic Inlines head. He was pretty interested in how it worked in a log head with a Weber because that was not the intent of the design. It should work really nicely in yours but then again, I would think the stock camshaft will work really well too.
 
I have a CI aluminum head # 035. I ran it 10 minutes on my 200 build before the lobes on the cam rounded off and the engine quit running. My fault, trying to break in a new Clay Smith cam and lifters with dual valve springs. I bought a 65 long block with good compression, adjustable rockers. I put the block on an engine test stand, connected all the systems and tested them, everything is functional. There is 120 lbs compression in each cylinder, 30 psi oil pressue at ifle, 50 psi at 250o rpms. No smoke no knocks or clatters. Now I have pulled the stock head and am preparing to install the aluminum head, 4bbl intake and headers. I am keeping the stock, all ready broke in cam snd lifters. What fo you all think of this plan?
For what its worth i say put a 2300 Sniper on it along with Hyper spark dist . Put a new timing chain in or at a minumin check it for slack then replace if needs be . I have been running the Sniper on my stock small log headed 200 for 6 years . Put a Paxton Supercharger on it about 2 years back . Both are excellent bolt on power adders . If you use the Hyper Spark try 12 degrees for start,24 for idle . I run 34 for cruise & 28 degrees for wot .
 
For what its worth i say put a 2300 Sniper on it along with Hyper spark dist . Put a new timing chain in or at a minumin check it for slack then replace if needs be . I have been running the Sniper on my stock small log headed 200 for 6 years . Put a Paxton Supercharger on it about 2 years back . Both are excellent bolt on power adders . If you use the Hyper Spark try 12 degrees for start,24 for idle . I run 34 for cruise & 28 degrees for wot .

Your ignition timing info is pretty invaluable and lines up closely with my observations.

This should be on a sticky somewhere for anyone who's trying to at least get into the ballpark on timing their L6 200:
  • 12 degrees for start
  • 24 for idle
  • 34 for cruise
  • 28 degrees for wot
 
Your ignition timing info is pretty invaluable and lines up closely with my observations.

This should be on a sticky somewhere for anyone who's trying to at least get into the ballpark on timing their L6 200:
  • 12 degrees for start
  • 24 for idle
  • 34 for cruise
  • 28 degrees for wot
I used those settings for a while before i put the Paxton on . Worked fine . It was pretty amazeing how much the eng smoothed out idleing useing that 24 setting . Keep in mind my eng is stock other than a few bolt on power adders .
On a small log head .

I hope it works for guys unlike me that have did the cam change,better heads with roller rockers . The good thing is if all the information has been imput in the handheld it should fire up & idle at the needed rpm for cam break in . .

I feel certain you would have to do some tuneing thru the hand held . But even if everything is out , if it cranks it should idle where you set it.
I wish someone had a dist. That could control the timeing like the hyper spark that was usable with a carb .
 
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