Good point...but as you say, it seems to work most of the time. I think the things you mention have a relatively small effect, compared to the wear pattern that was established on the cam and lifters.
Modern oil has ZDDP in it, just not as much as it used to have. And as blues pointed out above, adding more doesn't make things better on initial fire up, it just means that you can go a few thousand more miles on the oil. And all of us change our oil way too often in our hot rods, for that to matter!
Well, Blues, I got a problem! If it takes twenty minutes for the zinc to work?? The cam could/ would be gone by then! What up? Bones
"A band-Aid fix around 1980 , my uncle had a Pinto with a whipped cam , my father welding the lobes and filled shapes / lobe back by eye , cam lasted another 45,000 miles ." This sounds way more intriguing than the rest of this thread.
That would be why you use moly paste on the cam lobes, just as he said. Sent from my iPhone using H.A.M.B.
OK, hopefully not geeking out too much here, but to talk about this just a little, and maybe address the question from @Boneyard51 , the higher rpms may indeed improve splashing of oil onto the cam lobes, I can't say yes or no to that, though it seems logical, but the other reason this is important is because of what's known as "hydrodynamic lubrication". You can google that, verify I'm not making this shit up, but this is technically how lubricants work to prevent "sliding wear". Oil on the surface of the parts under a load, when the parts are moving (dynamic) the oil on the wetted surfaces forms a "hydrodynamic wedge", right at the point where the parts would make contact, that separates the parts and keeps them separated. It's connected to the non-compressibility of fluids. This is the mechanics of how lubricants prevent wear. It takes movement fast enough to develop that wedge, slower movement won't develop the wedge of oil. Really, it works in combination with the viscosity of the oil and is why the proper viscosity is critical to develop that wedge that keeps the parts separated. Here's an image that shows this in action. It's of a journal bearing, but the same mechanics would be at work between a cam lobe and a lifter.
I did call the tech man at warren oil company in Omaha, they have been selling their own oil since the 1920's. He said all the new spec oil are supposed to cover all classes of previous oils. but he did say it may be a good idea to use a heavy duty diesel grade of oil. so there you go, take your pick .I got the new cam and lifters in, engine is now tuned so it should start and run at 2 grand or so for 15-20 minutes. it is a 351c in a 1955 t-bird, and I really want to drive it before the snow flys!
@Blues4U C'mon man, Spare Us the tribology hermeneutics lecture. You're sposed to tell us what oil to use. We gots to know! "I only use triple filtered free range organic severely hydro-treated 00w-97 Valvostrolenezoil in my flat tappet engines". Thanks. (kidding, if anyone can't tell)
I think the gist of it is that you can use just about any modern oil, and it will work ok....but pay attention to what the folks who made the engine advise about viscosity. If you're breaking in a cam, there are more important things to worry about, than what brand of oil you have in the engine.
First and foremost , I would never put used lifters on a new cam. Something that has not been mentioned is lifter rotation in the bore...If the lifter doesn't spin on the cam it will eat the cam. This is really a problem on blocks that have been cleaned in a shot tank where the shot peens all the machined edges on the block, especially the lifter bore's...When I assemble a new engine with a flat tappet cam I always make sure the lifter rotates freely in the bore.
Yes! Lubrication aside: the Static coefficient of friction is greater than Dynamic coefficient of friction. Meaning that when the cam is running slower (closer to static), the friction between the mating lobe and lifter is more than when it is spinning faster (dynamic). That's another reason why you want to spin it up as soon as possible. Just like a burnout. Once the tires light up (dynamic), they spin easier the faster they go, because the friction is less than when it is sitting still (or static). That's why they have to spray them with water (lubrication) to get them to start spinning easier. After the burnout, the tire is now prepared for maximum traction (friction or stiction). Of course, heat is also built up in the process, adding even more friction. My 2 cents...
Yes! I agree. To clarify this more... This is a single valve spring with a dampener... do not remove the dampener. This is a dual valve spring with a dampener... do not remove the dampener.
Montana1 , I had no idea what you were talking about in your first paragraph!! Then in the last two....... I go argh! Ok..... I kinda get it! Thanks for splaning it for me! Bones
Blues4U, I want to believe you! I know you know what you are talking about.... but I can not abandon my real life experiences! Earlier this year I had the privilege of being a pit crew on one of the Outlaw guys on TV racing the 1/8 mile. The dude was running a 540 cubic inch big block Chevy that was super charged bad ass machine that was turning the 1/8 in 4.1 .... kinda fast! Well he was eating push rods on every run...... he was using the racing oil called Maxium , or something like that.... the best there is.... I guess! After we checked the valves several times, we had a pile of push rods and rockers, damaged! Luckily we still won the “ Shoot out”! But still had the problem! We added my additive to the engine oil.... nothing else.... and have not lost a push rod/ rocker arm since! That’s a lot of runs! .... a pile of broken parts...... to not problem at all..... the only change is an additive??? Tell me why this happens??? Bones
There is an old saying that rings in my head. It's not what you know in life that gets you into trouble it's what you think you know they is not so. Kind of like in life people get the right answers to the wrong questions and then base their decisions on wrong information. Jimbo
That's something that I might do if it was a steel cam you could weld it with hard surface rod and it wouldn't ever wear out. Need a nickel rod to weld a cast iron cam.
I think what your saying is the lifter is hydroplaneing on a wedge of oil between it and the camshaft?
I piped in a pressure gauge when I did my last pre-oil, I had 40 psi and was happy with that. I'd hit the 1/2" drill, made sure I saw oil at the rocker arm, rotate the engine a 1/4 turn, rinse repeat until everything was wet. I believe I went 2x around to get it all. VERY important to make sure the engine will run for 30 minutes. You can't be dicking around with it once it kicks over.
Lots of good info here, especially about lifter bore fit and ensuring that the lifters are free spinning. But to the point of trying to save a few bucks with used parts. What's the real cost? Should you quickly wear down a cam lobe all of that metal travels through the engine a bit before getting to the filter. It's probably not a short term failure, but it certainly starts things in that direction. So long term it's likely to be more expensive than the cost of new cam and lifters.
So in all this discussion , testimonials , guesses , and bs , no where do l see printed guidelines about how much the " proper" level of ZDDP in the oil is necessary , how much is in your favorite oil , how much is in the additives , how much is too much , how much is too little ? Numbers , precise , exact numbers , for example , 1200 PPM or 1500 PPM , enough with the conjecture ( that's the nice word for bullshit ) give me facts .I don't care what you've " heard " , show me in print! Documents from oil companies and component manufacturers. And just because you dress like a racecar driver doesn't mean you know anything ( i.e. Im not a doctor but I play one on TV ) LOL
Courtesy Chevrolet in San Jose, CA used to provide a can of STP with every over-the-counter 327 they sold, 1963-1967. A non-mechanic friend with a 'know-it-all' helper removed all the con rod caps, packed the bearing shells with STP, and retorqued rod bolts. Spun 2 con rod brgs. after startup, warranty provided another short block. Repeated procedure, same result, one spun brg. A meeting with the parts mgr. ensued, a third short block was provided. (???) Third engine lived, albeit without the 'assembly lubed bearing operation'. The cam was also wiped, but that was in the third engine, a month or so later.
Thanks to Blues4U for the oil information. Years ago I used a GM break-in oil additive, which I bought from the Chevy dealer, in a few engines and never had any problems with new cam/motor. I always did the 20 minute cam break-in procedure. Everyone seems to have their favorite oil. I never had good luck with Pennzoil or Quaker State. Went from Valvoline to Quaker State in a ‘51 Chevy and it started to smoke. Changed back and it stopped. I would never use combo of used/new cam parts. Too much hassle for too little savings to me.
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