I’ve looked, and most of the “parts” links are dead. All the discussion of cams is pretty complex with trying to achieve more hp I guess. The parts book for my 84 calls for part no. 4105 275. No dealer has one. My question is what is the absolute stock replacement? I don’t want this grind or that grind, or any more performance. I’m looking for the original reliability/simplicity/longevity. Just looking for a high quality replacement. Thanks!

Call Oregon Camshaft and ask for a stock 80s hydraulic lifter regrind cam. They should have the patterns.

Lou

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Home of Slant6-powered fun machines since 1988

You can still get a stock replacement made by Melling from Rock Auto SPD27 Hyd Lifter Camshaft for 1983 Dodge Truck 3.7L.

If you have a Mechanical lifter cam in your vehicle now, do NOT listen to or give any cam grinder this advice!!!!! Good Luck

Lots of them on eBay, brands like Elgin, melling

There were a few different grinds and some we're hydraulic while some showed as mechanical

I'd guess that any Rock Auto / Autozone etc. cam that is a 'stock' replacement will be a grind that is close to stock but a generic grind nonetheless. They probably catalog one grind for all years and we know that all years didn't use the same cam.

But....I wouldn't beat myself up too much over obtaining a stock grind. The idea that a stock grind will be better than an aftermarket grind is noble but won't mean much to your engine. If I was worried about reliability and all that I'd focus more on using a cam, and lifters, from a reputable place (like Oregon). That's more likely to result in reliability than worrying about the exact profile.

We know of a few different OE solid-lifter cam grinds, but I was under the distinct impression there was only one hydraulic-lifter cam. It's a weird emissions-oriented cam too.

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Joshua

Good point.

Is there something wrong with your cam? If not, then I would keep running it.

If I was going to the trouble of changing cams, I would never run a stock one. But that is your choice. I don't think a slightly larger cam will change your reliability one iota. If absolute reliability is the key, then I'd run the original I have. Good luck!!

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2 Mopars come with Spark plug tubes. One is a world class, racing machine. The other is a 426 CI. boat anchor!

12.70 @ 104.6

I don’t think theres anything wrong with my cam, but the intermittent valve tapping is pretty bad. I have most of the disassembly done, head off and everything. Can’t just put in new lifters without the cam though. The other thought is this: the stock replacement is a Melling CL-SPD-27 (cam and lifters) A replacement for an older solid lifter is Melling CL-SPD-3 are the pushrods the same? Could I just replace the rocker shaft assembly and use the older pre emission cam? And would there be any benefit to doing it?

The hydraulic valve gear is different from the mechanical valve gear. The pushrods, rockers and shaft are all different. You can retrofit a mechanical lifter cam, but you have to change the valve gear, lifters and cam.

The tapping may be just one lifter that's collapsing. You can check them and probably just replace the bad one or even disassemble and clean it.

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Joshua

Why not?

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Somehow I ended up owning three 1964 slant six A-bodies. I race one of them.
Escape Velocity Racing

that is correct,,and having driven the 83 D150 with the stock hydraulic cam, I cannot think of one reason to put that exact same cam back in.

But if the original poster want to do that, in my spare parts stash I have an new never installed OE grind hydraulic slant six cam. I got it from one of the RA close out sales maybe 10 years ago.
I bought it to have around to put a regrind on it, but if the original poster is determined to go back with a stock hydraulic cam, I can help make that dream come true. Send me a PM.

as an FYI listed below is the hydraulic cam valve timing
Intake Open 6 BTDC
Intake Close 42 ABDC
Exhaust Open 36 BTDC
Exhaust Close 12 ATDC

valve overlap 18
Intake and Exhaust duration 228

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Doo Ron Ron and the Duke of Earl are friends of mine.....
https://www.youtube.com/watch?v=uX8Nj8ABEI8

and one more thing,
Chrysler does not have a history of soft or improperly hardened cam lobs like GM does. There is probably wear on the cam shaft mechanical fuel pump lob, but I would bet that the actual cam lobs are fine. The fuel pump lob can be welded by a shop that does cam shaft regrinding.

If you have a lifter making noise, and it is a hydraulic lifter I would check the oil flow to the lifters as a first course of action.
Hydraulic slants are unusual in that they oil the lifters down through the push rods. I would take the valve train apart and verify
1) each push rod's through hole is open and clear, blow carb cleaner through each one
2) the oil flow passages in each rocker arm is open and clear, again, blow carb cleaner through each passage.

try and get the rockers and pushrods back in the same spot that they were in, probably not absolutely necessary, but a good idea.

re assemble the valve train and listen for noise.
If the noise is still present I would change out the lifters,
Follow a cam break in process with the new lifters

If the noise was still present, add a good mechanical gauge and check the engine oil pressure.
The oil pressure relief valve maybe stuck open and you have low oil pressure,,,
If you have never serviced the oil pressure relief valve, you should do that anyway,,,

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Doo Ron Ron and the Duke of Earl are friends of mine.....
https://www.youtube.com/watch?v=uX8Nj8ABEI8