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Re-Rebuilding the 440-493 in a 1970 Charger

I’ve always been one to overthink some things and grossly UNDERthink other things.
 
Cut and paste:

TECHTECH INFORMATION FROM MAHLE CLEVITE INC.For further information contact:TB-2078 Issued: August 16, 2001 Re-issued: May 10, 2010ENGINE BEARING FUNDAMENTALS PART 9 “CAMSHAFT BEARINGS”Most of the information published about engine bearings tends to deal with crankshaft bearings. Camshaft bearings are more or less taken for granted. We knock out the worn pieces, press in anew set and assume everything will end up the same as it originally was. This bulletin is intended to explain why this assumption is not necessarily true and why we should not just take cam bearings for granted. All but a very few cam bearings are bi-metal in construction and nearly all engines originally have their camshaft bearings installed in the unfinished condition and machined to size in the block as part of the block manufacturing process. This practice allows cam bearing ID’s to be closely controlled for size, shape, and alignment. In the rebuilding process we remove these “Finished-In-Place” (FIP) bearings and replace them with parts which have been “Precision” machined outside the engine. Replacing FIP with precision cam bearings introduces a number of variables not present in the original engine assembly. Originally, the clearance between the shaft and bearings was a direct result of the difference between the ID size the bearing was machined to and the shaft OD. When a precision part is installed its final ID size is determined by a combination of the manufactured ID size, the bearing’s wall thickness and the diameter and shape of the housing it is installed in to. These variables introduce a set of conditions we have little control over. If metal is shaved off the bearing OD during installation and builds up between the bearing and housing bore, the bearing will distort inward. If the block varies from spec due to distortion from overheating or the installation and removal of heads and manifolds, these variations will be reflected in the new cam bearings ID size and shape and ultimately in the bearing clearance and alignment. Main bearing housing bores are commonly reconditioned to correct for out-of roundness and misalignment. The same causes of distortion in main bores are likely to produce similar effects in the cam bearing bores. This explains why, after installing new cam bearings ,we sometimes encounter problems installing the camshaft Casual engine builders are often confused by the fact that the cam turned freely in the old bearings and refuses to turn in the newly installed bearings. First, remember that block distortion occurs gradually over a period of time, giving the camshaft the opportunity to wear the old bearings to match the distortion. Another factor is the relative skill or lack of skill exhibited by the installer of the replacement bearings. Nicks and dings will prevent the cam from turning.
 
I get distracted with other things.
Even though I changed the weight of oil and the pressure came up, I ordered a high volume pump from Summit. I was told that it would be coming from Ohio. A week or so went by and I got busy with other things. I called to see where the pump was and they said something went wrong with the order.
I figured I'd get back to this once I got a few other projects wrapped up. I've rebuilt the front suspension in a 72 Duster, done some things around the house and shop and worked on the 2007 truck....

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One of the reasons that I posted in this thread last night was because I am thinking about this project again.
When I had the engine out, I had considered the option of installing a roller camshaft. I had a solid flat tappet cam and matching lifters in the shed, a set that I had ran before when I had the 727. I pulled it because it was a bit too racy for my combination.

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I was then (and still am) nervous about the reliability of a flat tappet setup. Having a known good cam in place was the one advantage that swayed me. The high initial cost of converting to a roller also swayed me. I knew this Lunati was wilder than what I wanted but it was a safe choice. Most of the guys that I know have been okay with their flat tappet setups but it still digs at me.
This week a buddy brought over a 1990 360 that he didn't want or need. It is a factory roller cam version before they went to the "Magnum" 5.9 design. It got me thinking more about the swap to a roller cam in the 440-495.
One thing I'm going back and forth with is the lifters....solid or hydraulic?
One of the things that make a hydraulic tempting is that with no valve lash, it would run much quieter.
Yeah, I know....these are hot rods and they make noise. I don't mind most of it, in fact I love exhaust rumble and a bit of cam lope. It is the clickity-clack of valve lash that sometimes annoys me. I've heard that even the hydraulic roller setups have clatter. If that is due to the lifters, wouldn't a solid roller also have clatter but be simpler and cheaper?
 
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