Flat Tappet Oil

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Taylor

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IMHO any SM rated oil is fine for a flat tappet in it's stock form. However many engine builders feel that these *lower zddp* oils are causing cam failures, which I agree with to a certain extent. There are far to many variables in the real world to attribute these failures to one specific reason. Improper assembly, Cam MFG defects, underlying design issues, improper break-in, throttle happy motor heads, etc. But what about the "veterans" that are using the same procedure that they have been using for 50 years? And preformed hardness tests, UOA's etc? Somewhat suggestive?

To my understanding API no longer test for flat tappet performance, but A3 oils do? So would an A3 oil be a good choice for us flat tappet guys? What other choices are there?

IMO there are other adds than ZDDP that can handle Hi-Pro motors. Am I correct? If so which ones should we look out for? Boron, Antimony, MoDTC?
 
Also there have been some stock failures, the first thing that comes to mind is maintainance. But when I suggested SM oils were sufficient for stock flat tappets someone argued that these camare still in service due to the fact that they were run on the oils of yesteryears with higher ZDDP, and have hardened over time. Is the possible?

My reason for asking is, I am getting ready to put together a 4.6L stroked w/ a fairly aggresive cam. And the first roller for this engine (Jeep 4.0) was recently developed, but it is a hardened stock re-ground (cast-iron) and it is a bit pricey.

Thanx in advance!
 
If it were me, spending the money/time/care to build a custom engine, I would not try to save a penny on the first few hours of that engines life.

I would run the engine in, standard load-cool run in, with a high ZDDP, synthetic, not conventional, motorcycle oil. Mobil 1 10W-40 has a 1600 ZDDP level, higher than the diesel oils. Amsoil 10W-30 and 10W-40 motorcycle oil has a 1340 ZDDP level.

After the initial run in, I would change the oil and filter. I would go 500 miles easy break in, same high ZDDP oil, and then change oil and filter again. This time I would go 2,000 miles, a little more aggressive break in, then change oil and filter, same high ZDDP oil. From this point you will have to determine OCI based upon your use.

The only downside to the motorcycle oils is that they do not have friction modifiers, but, neither do the majority of the diesel oils, and those that do have very little FM.

Some folk say you can/should not run in or break in an engine with synthetic oil. This is one of those myths. Synthetics take longer for break in but give a smoother surface more even surface, at least according to GM. I change the factory oil out the minute I get the vehicle home from the dealer and put in synthetic. I have put 170,000 to 300,000 miles on many engines doing this. Corvette even uses a 5W-30 synthetic as part of their assembly lube.

Enjoy a long trouble free life with your custom engine.
 
I'm not looking for a break-in oil. More along the lines of and oil (or rating) I can run long OCIs with, after break-in, worry free. It doesn't need to be but preferably OTC, REGUARDLESS of ZDDP levels. I have done the whole "quest" for high ZDDP oils and additives. I know ZDDP is kind of cheap insurance for such an investment, but I want to move away from this, and possibly disprove some of the myth, at least to myself.

In my stocker I plan on running Fuchs Titan 0w20 (zinc free), as it meets 30w HTHS min.
 
Taylor, I studied the issue awhile back. See here:

https://bobistheoilguy.com/forums/threads/reduced-levels-of-zddp-in-sm-oils-issue-or-not.66168/

Bob Olree's comments and a url to the ASTM REPORT
Development of the Sequence IIIG Engine Oil Test is included.

Most insightful post in the thread came from a guy doing race engines. It's copied here.

===========

Mitch Alsup
Registered: 04/25/05
Posts: 450
Loc: Austin Texas

Our shop has had trouble with an old 2.6 litre Porsche engine making 280 HP at 8,700 RPM on 113 Race gas. We used to get 40 hours on an engine and never had an early failure in 5 years of racing, and when SM came around (M1 20W-50) we lost 4 engines in 3 hours! (15 minutes on the track and they were way off tune) Eating cam lobes was typical, but bearing scuff was also a lot higher than normal. When we started to add EOS durring break-in (which takes place on a dyno) our issues went away.

I know this is a far cry from anything streetable.....

========

My conclusion on non-stock (aggressive) cam/springs require special ZDDP/Phosphate attention during break-in but not afterward.

I have been using 700-800ppm ZDDP oils in my '85 911 for about 20K miles. Did a valve adjust shortly after starting it (cams looked great at ~170K miles)but have not gone back in yet.

In these cases you're doing your own engineering so it's good to consult people with specific experience in your application.
 
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Hey Glen, thanx for the post! On a side note, what's going on with the bimmer?
 
I know this subject is covered often, but I was hoping to be a bit more specific and in depth that "is SM ok for my 4.0?"

Anyone else? Gary? Mola?
 
So SM does test on flat tappets, I'm curious as to what the cam specs and valve spring pressures are?

So the claim is SM is sufficient even for a "hi-pro" motor, but only after break-in obviously. Hmm
 
Originally Posted By: Taylor
IMHO any SM rated oil is fine for a flat tappet in it's stock form. However many engine builders feel that these *lower zddp* oils are causing cam failures, which I agree with to a certain extent. There are far to many variables in the real world to attribute these failures to one specific reason. Improper assembly, Cam MFG defects, underlying design issues, improper break-in, throttle happy motor heads, etc. But what about the "veterans" that are using the same procedure that they have been using for 50 years? And preformed hardness tests, UOA's etc? Somewhat suggestive?

To my understanding API no longer test for flat tappet performance, but A3 oils do? So would an A3 oil be a good choice for us flat tappet guys? What other choices are there?

IMO there are other adds than ZDDP that can handle Hi-Pro motors. Am I correct? If so which ones should we look out for? Boron, Antimony, MoDTC?


If you're looking for a good additive for flat tappet engines check out Redline Break In oil additive. It can be used as a break in add as well as an add to beef up the ZDDP levels in any oil. Their part # is 81403. I've discussed the product with them and it will fit the bill for you. HTH

It is a ZDDP add..
 
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Originally Posted By: Taylor
I know someones got the answers!


I use Trop-artic syn-blend on my stock flat tappet motor with stock valve springs...I think it has a decent amount of ZDDP (maybe 6-700 range)for the OCI interval I use (every 4k).

There are many people who have gotten 300k + out of 4.0L Jeeps with cheap dino oil every 3-5k...and for part of that time they would have been using SM oils.
 
I run SM 5W30's in my Jeeps for winter. I've never had any problems or excess wear. There are probably millions of 4.0L's and 2.5L's running SM.
 
Originally Posted By: Taylor
I'm not looking for a break-in oil. More along the lines of and oil (or rating) I can run long OCIs with, after break-in, worry free. It doesn't need to be but preferably OTC, REGUARDLESS of ZDDP levels. I have done the whole "quest" for high ZDDP oils and additives. I know ZDDP is kind of cheap insurance for such an investment, but I want to move away from this, and possibly disprove some of the myth, at least to myself.


While I am looking for an oil for a hipro motor with agressive cam grinds (flat tappet) and high spring pressures. I am also looking for answers to questions listed in the 1st post. Thanx
 
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Valvoline VR-1 is a good choice, I ran this for about a year in my '67 mustang, I will be switching over to M1 5W-40 turbo diesel when I get it back from the paint shop. Neither one of these need additional ZDDP, their both in the 1300 area. The VR-1 should probably be changed every 6 months or so, that is one reason I'm switching over to the M1 diesel.
 
VR-1 available as straight 30wt, 40wt and 10W-30 plus the 20W-50,maybe available in others I haven't really looked as I always used the 30wt or the 10W-30. I think the M1 5W-40 is a decent range for most of the older V8's, I'm switching over to this (besides ZDDP) because I run it in my diesel tractor also..keep it simple.
 
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