FT cam break in "non detergent" oil

Joined
Sep 30, 2004
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35
Location
Gainesville FL
I get that flat tappet break in oil should contain elevated amounts of zinc and phosphorus. What I don't get is why there are various videos on YT that say "Don't use a detergent oil, the detergent will wash off the additives and your cam will go flat"...

Now, the only non detergent oil I am aware of is the SA and SB grades which don't contain a modern day add pack. How can there be an oil which contains all the additives necessary for flat tappet break in but not be a "detergent" oil?
 
"Don't use a detergent oil, the detergent will wash off the additives and your cam will go flat"
Forks also make people fat, did you know that?

There is such a thing as surface competition, but a properly formulated and tested engine oil doesn't contain additives that "wash" the anti-wear additives off.

It's highly unlikely that you will find non-detergent oils that have the proper amount of anti-wear additives for engine break-in, unless it's an oil specifically formulated for break-in and I'll bet they have detergents.

Too much of an anti-wear additive can be detrimental as well. It's a careful balance.
 
Detergent "wash off" sounds like a crazy theory to me. This will be the second flat tappet cam in 30 years I will break in. I broke the last one in on Syntec 20w50 in 1992 and it did not go flat. I am planning on using Rotella 10w30 dino for this session.
 
I get that flat tappet break in oil should contain elevated amounts of zinc and phosphorus. What I don't get is why there are various videos on YT that say "Don't use a detergent oil, the detergent will wash off the additives and your cam will go flat"...

Now, the only non detergent oil I am aware of is the SA and SB grades which don't contain a modern day add pack. How can there be an oil which contains all the additives necessary for flat tappet break in but not be a "detergent" oil?

They're technically correct, but wrong about why. Overbased detergents are acid neutralizers. ZDDP is an acidic ester. You can see how they don't like each other. Balancing them is a big part of oil formulating, and also why I never recommend playing backyard chemist with a supplement.

During break-in, we have no use for a lot of detergents since the oil isn't run long enough to matter. Best to have a load (2500-3500 ppm) of highly reactive, branched secondary alkyl ZDDP, that'll form a thick anti-wear film at lower temperatures and friction, and get everything else out of the way. A small amount of neutral calcium sulfonate can help ZDDP disperse and stabilize tribofilms. Just a note on how elemental analysis isn't always what it seems.

For example, Driven BR30 break-in oil is....

Zn - 2833
P - 2560
Ca - 348 (neutral)
Mg - 0
Mo - 0
B - 0

TBN = 1.96
TAN = 5.4
 
The Cam manufacturer will usually want to include a break in supplement. You could add this to an SAE 30 ND monograde oil
or a motorbike 4T conventional or any non LL oil of your choice. I Just broke in a small cam a couple years ago on a HP Buick small block, I use 2/3 of the break in additive for the run in, then put the other 1/3 leftover in the fresh oil after I dumped the break in oil and changed the filter.

I wouldn't go nuts "grilling" your cam on your smoker and basting it with lard. That is likely unnecessary : )
If you are street/strip or strip or roundy round you should run a rollerised valvetrain if allowed in your class.

- Ken

WP_20200216_14_25_58_Pro.jpg
 
I am doing the obligatory Chevy 350 crate motor upgrade. New Vortec heads, and replacing the stock flat tappet with a very small Lunati flat tappet cam. I have new hardened face GM lifters and will check that each lifter rotates before starting the engine.

It seems that by the time you install the cam, rotate the engine to set valve clearance, etc. most of the lube is wiped off anyway.
 
It seems that by the time you install the cam, rotate the engine to set valve clearance, etc. most of the lube is wiped off anyway.
True, but there will still be a fine film on the lobes until it is 'washed' off by oil. Kinda like car wax, you can lay it on as thick as you like, but after you rub it off what's left is a thin layer.

Many years ago, one of the rod mags polled quite a few of the top engine builders about break-in lube. IIRC about 3/4 of them indicated they used ND30 and some kind of zinc/moly additive package. When asked why, the typical answer was - That's what we've always done.
 
???

Run break in oil and load-er up with moly lube on the new parts.
 
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