cmrris

I have a 360, running magnum heads. The first time I had this engine together, I got about 800 miles before a lifter completely wore through. I would've checked it out before it wore a hole if I had realized the ticking noise was the lifter and not an exhaust leak, I had even planned on ordering a new header gasket that night. I tore it completely down, cleaned it and replaced all the bearings. In went a new comp cam. Break-in went flawless. Got about 150 miles on it and I can hear the ticking coming back. I'm thinking it has too much valve spring and I'm getting on it too hard too soon after break-in both times unfortunately. It's been parked since while I try to figure out what to do because I really don't want to tear it down again so soon. I plan on pulling the intake and seeing how bad it is. I know the best thing to do is to pull it and clean it, but it has a nice K&N Performance Gold oil filter on it and it was barely run. Any thoughts on what I'm thinking about doing? -Check out the cam, if it's not terrible then drain oil and check filter, circulate/flush oil system, new cam and lifters. If the cam is crapped out, I'll just pull it and set it in a corner until I feel I working on it again. Any tips, do's and don'ts?

Iowan

How big is the cam you have been trying to use with your Magnum heads?
Stock these heads don't allow for much cam lift and you could have some binding in the valves or valve springs.

cmrris

I'll need to pull up the cam specs, but I triple checked everything and used the hughes magnum springs and retainers that everyone recommends to use. I'd be embarrassing for that to be the problem with how much I reseached

cmrris

comp kit CL20-223-3

Intake Duration at 050 inch Lift:224

Exhaust Duration at 050 inch Lift:230

Duration at 050 inch Lift:224 int./230 exh.

Advertised Intake Duration:268

Advertised Exhaust Duration:280

Advertised Duration:268 int./280 exh.

Intake Valve Lift with Factory Rocker Arm Ratio:0.477 in.

Exhaust Valve Lift with Factory Rocker Arm Ratio:0.480 in.

Valve Lift with Factory Rocker Arm Ratio:0.477 int./0.480 exh.


So with the 1.6 ratio magnum rockers it would be 0.509/0.512, which shouldn't be a problem from everything I've read.

Coronet 500

Cut open the oil filter and spread out the media to see the good or bad news. I always take the time to break in a cam with light springs, then change to the heavier. It sounds like a lot more work but after you've done it once, like anything, next time is real quick. Maybe I'm just fussy but never had a problem yet.

Also I've got sets of very light test springs which makes checking geometry and valve guide to retainer clearance easy. Chrysler machining on heads was very inconsistent and sloppy in some cases.

cmrris

I pulled the intake off and removed the rockers and pushrods and pulled out and checked the lifters one by one- all lifters are prefect, no doming on any of them. The cam looks alright from what I can see, I'll turn the engine over to check it out more later today. Next I guess I'll check the pushrods for straightness.
I'm a little baffled- it had a low rpm tick and stumble, but so far everything checks out good. I'll keep updating as I find things.
I'll attach pictures so yall can give your opinions

Coronet 500

You do have push rod oiling with oil through lifters I assume? Sorry In had to ask. Now would be the time to put in a couple light test springs and check geometry and retainer to guide clearance, cover all the bases.

cmrris

Yep. Needed shorter rods to use the magnum heads and measured it the first time with the purple cam and Mopar lifters I was using. Boss 302 pushrods were darn near perfect, and since they were and off the shelf part I went with those instead of custom made ones. I wouldn't think the comp cam and lifters would be too much different but I guess it wouldn't be hard to double check that.

RacerHog

That don't look to bad from here....
Hummmmm.... Check and make sure the lifter's are not unshrouding out of the lifter bore on the top side and on the bottom side. Just food for thought...

TVLynn

If you wore thru the lifter the cam is probably junk ???.. NOT enough zinc additive for break in

cmrris

That was the first cam. I tore it down, cleaned and rebuilt it. Only used comp breaking oil and their additive since.

cmrris

Would it be a possibility that maybe I didn't have the block completely cleaned or something and maybe there is some junk stuck inside a lifter that's causing it to not pump up properly at low rpm? the lifter bores all still look good.

Coronet 500

Sure possible but LA block oil could get blocked and starve one side making lots of ticking. Push rod oiling could be a few blocked and be a tick hear and there if you get where I'm going, it depends on how much ticking. You could remove distributor and pump oil with a drill to see if you have it at all lifters then put rods and rockers on to see if each one has oil at the valve stem before tearing everything apart.

cmrris

I couldn't find anything wrong, everything seemed to be working how it should. I put it back together and here's a video of it running. The ticking sounds worse on the video than it really is, but it's still there.
https://photos.app.goo.gl/UtfaV8Bs6MWtIlI02

RacerHog

Sounds to me like a exhaust leak or valve adjustment is out of spec.

Coronet 500

I agree with Bob. A mechanics stethoscope will narrow it down and not expensive tool.