DC Mechanical Cam & Spring Questions

[Flying G]

Greetings. I'm building up a 360-based 410 for an A-body with a manual transmission, mostly for street duty. This is a project my father started before he passed. He had collected up a lot of parts, including a DC mechanical cam P4120653 (284 deg adv duration, .528 in. lift), which I'd still like to use.

1st problem: The cam has been sitting for a few decades & has some rust spots on it. My machinist told me to run it & not worry about it, but I'd like y'all's opinion.
>> Is this still OK to use? >> What's the best way to clean it up?

2nd Problem: The valve spring Mopar recommends for this cam, P3614542, doesn't seem to be available anymore. The "2nd choice" spring, P3412068 is still available, but seems to be more of a max-effort spring for lifts up to .630 in. Mopar never gave spring rates or pressures. I also need valves, retainers, etc., so I called Mancini for a quote. They spec'd Comp Cams spring 995-16 with a spring rate of 402 lb/in., which is the strongest spring listed on their website. That, too, seems like overkill.
>> Based on the cam specs & application, what's the right valve spring?
>> Is anyone else running this cam? What springs are you using?

Thanks for the help!

 

[RustyRatRod]

I would hit it with some PBlaster or similar and run it. That's probably the best street/strip flat tappet cam ever made for the small block. The 995 seems appropriate.

 

[Bewy]

OK to use.
Notice the groove in the cam journal? I have seen one in a DC cam for a hemi, first time for the 340. Full time oiling for the top end. Chrysler thinks the top end needs more oil while a lot of people try to restrict the oil flow.

 

[GTX JOHN]

Anu brand spring that will set up @120 to 140 seat and
approximately 300 @ full lift is what I would run on that cam
and I have run several of those.
Like any HP setup I would not let it idea for extended periods
of time

 

[340dartsport73]

Its been awhile, but if I remember right I ran comp cams 924-16 springs with that cam with no problems in my 340. Rev past 7k no problem.

 

[Flying G]

Thanks for the input, gents.
I will go with the 995-16 springs & have the shop check them at full open & closed.
Btw, Bewy, I had my machinist cut the grooves in the no. 2 & 4 journals.

 

[RustyRatRod]

Thanks for the input, gents.
I will go with the 995-16 springs & have the shop check them at full open & closed.
Btw, Bewy, I had my machinist cut the grooves in the no. 2 & 4 journals.

Make sure they check retainer to guide clearance too. The guides may need to be cut down some.

 

[rumblefish360]

Run the cam without care or concern.
Get the MP springs and disregard your “Max Effort” thoughts on it being overkill. What the upgraded spring will do is allow more rpm. And you’ll like rpm with that mechanical cam. A lot!