Question on oil for flat tappet camshaft.

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I know i know, you read the title and you think here we go again. Trust me i feel the same way. I bought a new camshaft for my sbc 350. It’s going in my stock 78 k20 truck. It’s a melling ccs-2. Just a stock replacement. I’m not looking for any in depth analysis here on what oil i should use. Basically every hotrod forum freaks out about limited zinc and phosphorus in these modern oils and says you have to run zinc additives otherwise the cam will get wiped out. but i know from being on this forum long enough that modern oils are fantastic and there are different anti wear additives that people don’t think or know about that protect as good as the old oil. Essentially am i ok with running a normal generic modern oil or will i need to add zinc additives every oil change in order to keep my cam alive? Ps. I will be breaking it in with assembly lube and zinc additives.
 
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The cam manufacturer should have break-in instructions. I would run a high zinc oil at least for break-in. Don't let it idle during initial start up, 2k rpm first 20 minutes.

BTW, new lifters with that cam?
 
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An engine shop I know recommends 0W40 Mobil1 for his builds. He also breaks-in high lift cams with lighter valve springs and switches to stiffer springs after break-in. Mobil1 0W40 is a full saps Porsche A40 spec oil, so it's not lacking zinc or protection.

I doubt you bought a lumpy cam needing stiffer valve springs to go through all that?
 
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Something that is always relevant. ZDDP is for when viscosity is insufficient to do the job. Clean oil, of sufficient viscosity, and at reasonable temperatures will always be important.
 
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In my past I rounded several Chevy cams. And was long before the lowered ZDDP came about. The last one I used a break in addative and a regular oil. Iirc it was sae30.
Chris, Did the last cam last? Sounds like if the seals can handle it, the 0W40 would good, but I doubt they will stand up.
Superbike or ATV "conventional 4T" oil rated API SG/SH/SJ or SL or for guys with built RV BB, Quicksilver Mercury inboard 4 stroke 25W-40
OTW just add a bit of Lunati break in additive to a sump of whatever oil you choose at each OC.

In the Seventies, just about any GM car I serviced over 80K miles had a couple wiped lobes when I did timing set and water pump replacement which were also trashed. a couple burnt valves too.
 
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Break in the cam per instructions with break in additive. I would then run a good 10w30.
Make sure distributor is set to fire and you have fuel so you do not have to over crank engine. Get it up to speed.
Have fun with it!

You said stock replacement; as long as your springs are stock, you will be fine.
I like Melling cams.
 

OVERKILL

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A stock SBC cam doesn't require anything special but if you want to be "extra safe" a Euro 0w-40 or 5w-40 that's full SAPS would be a great fit. M1 0w-40, which was recommended above would be my choice.
 
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Chris, Did the last cam last? It was ok when I sold that car. I bet I put 5 cams on that post in about 3 years. The 302 in my Ford ate a cam as did the 340 I had.

I have no luck with v8 cams! All were broken in per directions with an addative. The last one was a BlueRacer" brand. They were specially ground with more taper to allow the lifters to spin better.
 
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Aren’t most cars flat tappets that ride on the cam lobes and also made to rotate? What is camshaft break in exactly? Take away the very fine machining marks?
 
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Aren’t most cars flat tappets that ride on the cam lobes and also made to rotate? What is camshaft break in exactly? Take away the very fine machining marks?
Ya basically. The lifters mate with the lobe. Once mated you can't or should not mix them up and use them on a different lobe. Old school v8 engines lubed the cam and lifters with oil that gets thrown off the crankshaft. They require about 2000 rpm to throw enough oil onto the cam and lifters.

Idling an engine with a new cam and lifters instead of 2000 rpm will wipe them out in just a few minutes.
 

joegreen

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Break in the cam per instructions with break in additive. I would then run a good 10w30.
Make sure distributor is set to fire and you have fuel so you do not have to over crank engine. Get it up to speed.
Have fun with it!

You said stock replacement; as long as your springs are stock, you will be fine.
I like Melling cams.
Yes the motor currently runs in my truck its just the current cam has some bad lobes. So it should fire right up with the new cam.
 
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In my past I rounded several Chevy cams. And was long before the lowered ZDDP came about. The last one I used a break in addative and a regular oil. Iirc it was sae30.
In general, flat tappet excessive cam wear is caused by the loose nut behind the wheel and his/her lead foot. Read overly high rpms
 
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The

Ya basically. The lifters mate with the lobe. Once mated you can't or should not mix them up and use them on a different lobe. Old school v8 engines lubed the cam and lifters with oil that gets thrown off the crankshaft. They require about 2000 rpm to throw enough oil onto the cam and lifters.

Idling an engine with a new cam and lifters instead of 2000 rpm will wipe them out in just a few minutes.
This! You need the oil thrown on the cam. Cam mates to the lifters. I've used new lifters with a good used cam but not a new cam with used lifters new cam needs new lifters!

Break-in mates the cam and lifter faces. I think it burnished in the cam lobes a bit.
 
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If you need "high zinc" oil because you are drag racing or something, be sure and NOT use the HDEO oil. The high amounts of detergent literally displace the zddp molecules, rendering a 1400 zddp oil no better than a 700 zddp off the supermarket shelf. By "no better" I mean no better in the ZDDP department.
 
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