Technical question on "mild cam"

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Woodsman341

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I recently bought a '75 Dart Sport with a 360. The guy I bought it from said it "has a mild cam", but he didn't have specifics because the guy HE bought it from didn't say. The engine runs great, currently, but I intend to tear it down when I strip the body down for paint. Now, the question:

How can I tell what cam it is, so I can get proper specs on valve adjustment? I'm new to non-stick internals.

I thought about just measuring the valve lash as it sits, just to get a ball park. Either that, or sink the money into a new cam, lifters, rods, er cetera, but I really don't want to spend that much if I can help it.

Thanks!
 
Woodsman341 said:
I recently bought a '75 Dart Sport with a 360. The guy I bought it from said it "has a mild cam", but he didn't have specifics because the guy HE bought it from didn't say. The engine runs great, currently, but I intend to tear it down when I strip the body down for paint. Now, the question:

How can I tell what cam it is, so I can get proper specs on valve adjustment? I'm new to non-stick internals.

I thought about just measuring the valve lash as it sits, just to get a ball park. Either that, or sink the money into a new cam, lifters, rods, er cetera, but I really don't want to spend that much if I can help it.

Thanks!
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Unless you measure it you won't know what it is. Lift is easy with the valve cover off. Duration is more complicated to measure. Otherwise you have to take it apart and look for numbers.
 
toolmanmike said:
Unless you measure it you won't know what it is. Lift is easy with the valve cover off. Duration is more complicated to measure. Otherwise you have to take it apart and look for numbers.
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I will be taking it apart, I just wasn't sure if it would be stamped with any identifying information or not.
 
there´s only valve lash when a solid lifter cam is installed including the solid lifters. You should check if you have solid or hydraulic lifters as a first step.
 
360duster said:
there´s only valve lash when a solid lifter cam is installed including the solid lifters. You should check if you have solid or hydraulic lifters as a first step.
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That's odd - I swear I had to adjust the valves in my original '75 Dart 360 (back in the early '80s). Maybe my memory is faulty? Or are you saying that if I did, I had solid lifters, and that with hydraulic lifters I wouldn't have to adjust the valves? I haven't been inside an older engine in a long time...just in case it doesn't show. :) My last several cars were All imports with all the self-adjusting stuff.
 
You could just measure the lift with a dial indicator on one intake and one exhaust lobe. I had a friend with the intake off - the purple dye and lift told us it was a Mopar 484" grind. Got lucky, but the odds are against that.
 
Pull a valve cover off and look for adjustable valvetrain. If someone stuck a solid cam in it, and it needs lash adjustment then adjustable rockers will be there. If it has non adjustable factory type rockers then the chances that it has a hydraulic cam in it is about 99.9% and won’t need adjustment. But I have a question for you, you said “the engine runs great, currently…”. If that’s true why are you tearing it down?
 
If you are tearing it down... usually quite a bit of info etched on the cam itself. This is what was on the back of the Comp I put in my BB Ford.

IMG_2344.JPG
 
TT5.9mag said:
Pull a valve cover off and look for adjustable valvetrain. If someone stuck a solid cam in it, and it needs lash adjustment then adjustable rockers will be there. If it has non adjustable factory type rockers then the chances that it has a hydraulic cam in it is about 99.9% and won’t need adjustment. But I have a question for you, you said “the engine runs great, currently…”. If that’s true why are you tearing it down?
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Well, there are other things the previous owner said that I have since found out were either incorrect or deliberate falsehoods. :) There's a bit of a fumey (fume bases?) cloud when it's running, and it is most likely just running rich, but I plan to at least get into it a bit to judge for myself if there's sludge, if the rings/pistons/cylinders seem alright. Plus, I'd hate to get it all together just to have something go wrong that I could have prevented, ya know?
 
Woodsman341 said:
I really don't want to spend that much if I can help it.

Thanks!
Click to expand...

if it runs great, then just get a baseline: compression test, leak down, visual on the cam situation (hyd or solid) check the lift. from there you can focus on tuning and eliminating the "fumey" situation.

if you pull it and open it you'll let the magic out and then be left with an empty wallet.

I'd do the above and roll while building a another motor on the slow boat, picking up deals along the way to make it happen.

then again, it depends on the time line for paint and body work... might have some spare time on your hands.
 
junkyardhero said:
if it runs great, then just get a baseline: compression test, leak down, visual on the cam situation (hyd or solid) check the lift. from there you can focus on tuning and eliminating the "fumey" situation.

if you pull it and open it you'll let the magic out and then be left with an empty wallet.

I'd do the above and roll while building a another motor on the slow boat, picking up deals along the way to make it happen.

then again, it depends on the time line for paint and body work... might have some spare time on your hands.
Click to expand...

Excellent advice. I already have a line on another 360 and/or 340, so... :D
 
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