351C-2V Camshaft help.

[freerobotsex]

I am rebuilding a 1970 351C-2V and need to replace the camshaft because the stock one has pitting on the lobes. I plan on adding an Edelbrock Performer intake manifold, Blackjack headers, and a Holley 650 cfm 4150 carb.
As for the heads, I will have them re-surfaced with hard valve seats installed for unleaded fuel, new guides, valves and seats ground, plus heads machined for positive lock valve seals. I would like to use the stock rocker arms, pushrods, and valves if I can but I understand I'll need to use new lifters and springs. I've been looking at the CompCams High energy and Dual energy cams but all of them require screw-in studs and guide plates plus machining on the cylinder heads. Also they require multi-groove valves. I believe the 351-2v stock valves are multi groove. Why would I need screw-in studs? Would that require machining of the heads? Can I use the stock rocker arms with the screw-in studs?
Any help or thoughts would be appreciated.

 

[67efivert]

as long as u pick a mild hydrualic cam u can use stock valvetrain
the multigroove valves that came stock are prone to stripping the locks out most people use new single groove valves during a rebuild

 

[freerobotsex]

I mis-understood the CompCam information. Screw-in studs and guide plates are recommended for their rocker arms not the camshaft. Their valve locks are for the multi-groove valves. This makes more sense. When picking a camshaft should I be concerned about valve to piston clearance? Or is that a problem only in the most radical cams? Any good mild cam suggestions would be appreciated. I'm looking right now at the CompCam Dual Energy Hydraulic Flat Tappet #32-207-3 265DEH grind.

 

[htwheelz67]

I would run a comp cams 268h , easy on the valvetrain, works great with 9.1 comp or less and you can use stock rockers and it will give a nice power increase but still give as good or better fuel economy than stock.

 

[91dawg]

the comp 268 is a good choice... how much lift will u run? If I remember correctly I ran an elderbrock 268 with .5 lift in my '73 and it ran great with a nice lope at idle

have fun

 

[ddonaca351]

The search function is your friend, we just went through this about 7-10 days ago.

Links to parts listings, etc... all included in that thread.

Op was 73xxxxxx something screenname

EDIT: I lied... two weeks ago; here
http://www.stangnet.com/mustang-forums/796362-351c-2v-build-up.html

 

[freerobotsex]

Thank you. I did do a search and read that thread, but it didn't address my original question about the guide plates and screw-in studs.

 

[68RCodeConv]

I recommend against using the 40 year old stock valves. They have a nasty habit of coming apart - especially with the higher spring rates used with aftermarket cams.

That will ruin your whole day.

 

[ddonaca351]

Fair enough...

Dont use the stock valves, they have been known to come apart in higher rpm/higher power applications. Plus they already have 30-40 years worth of wear and tear on em.

The newer cams use quicker ramp rates, higher lifts and longer duration than stock cams, thus generate more load on the valvetrain.

The stock design of rockerarms, bolt down mounting, etc... are to do a job "ok" as cheap as possible.

Using screwin studs and better rockerarms not only reduces parasitic losses (it takes power to overcome friction) but it ensures longevity. Once something binds, for even a fraction of a second, it usually gauls... then proceeds to self destruct right after that, taking everything else around with it.

If you want a "stock" level rebuild, just use NEW stock replacement parts. (modern metalurgy, production, QC, etc... has advanced a little in the last 40 years)

BUT if you're gonna use stock valvetrain, (imho) I would go conservative on the camshaft.

( note: stock rebuilt heads and conservative cam = weak suck power levels and years of kicking yourself in the ass, for not spending the extra $8-900 and getting 100 hp more. )

 

[D.Hearne]

Here's another good choice for a stock cam replacement Summit Racing's K5200. I used this one in a stock 400M. Really woke it up. Works with the stock valvetrain too. Replace the valves and rocker fulcrums with ones from a 79-82 351M/400. Your Fulcrums are aluminum, the 79-82 351M/400's had iron fulcrums.

 

[freerobotsex]

Thanks!