ZDDP again

[evelrod]

Just picked up several gallons of motor oil to restock from my annual oil change regatta---(well, it SEEMS like I'm sailing in a sea of oil by days end ;o( ---too many vehicles around here). I noticed that there are several brands of ZDDP additive available. Average price is around ten dollars. OK only for off road, racing, agricultural, etc.---Pre OBD stuff.
It looks like it might be the hot setup for some of our vintage, flat tappet cammed cars.

Anybody tried this additive lately? I'm still using, on my diesel and vintage engines, Castrol 20W-50 as it still (so far) has sufficient additive.

Rod

 

[drwebb]

As I have alluded in other posts, from a formulation viewpoint I am skeptical that lower ZDDP is the root cause for two reasons:
1) Service classifications are defined mainly by oil performance and not chemistry. That means that API-licensed engine oils must have passed stringent engine Sequence tests specifically designed to gauge cam wear. This is the technical basis for recommending the latest categories as "backwards compatible" to older engines designed around previous service categories. While phosphorus content is limited in the latest categories, there has been no lessening in requirements for demonstrated cam wear protection.
2) The anti-wear effects of ZDDP tends to saturate at fairly low treat levels. This means that only a small amount is 'active' at a time, so a significant portion in 'older' formulations was there for oil performance durability over the course of the oil drain intervals. Break-in service is normally a short interval, so probably not all the ZDDP in the old 1200 ppm P oils was necessary for break-in protection.

There are a few specialty marketers who cater to the 'more is better' formulation strategy and advertise very high levels of phosphorus or zinc in their formulations. You can find one of these and try for yourself. Since such products are available, if high ZDDP were an effective fix for HP cam break-in problems word would get out that they are the solution. As that apparently has not happened then I suspect oil performance is a convenient scapegoat when there is a problem, because it's something the hard parts guys claim they can't control.

 

[evelrod]

This is as good a place as any---Several racer/engine builder friends of mine and I have had an ongoing discussion directly relating to break in procedures...including the "ZDDP" question. One of the contacts is familiar with the NASCAR engine building/break in procedure, but even he cannot find exactly what formulation they are using. "0" viscosity? Special formula,ie, home brew? (assuming all use a similar product???)...They seem to have few engine problems and they twist those 358 cu.in., pushrod, 1964 era engines to ten grand with flat tappet cams!

Our current search is to find out what oil pressure they are running. I'm told the old Smokey Yunick 10psi/1000rpm is out and dry sump with as low as 35psi hot is in. The claim is a savings of 7 to 10 hp.
Anybody got a better take on this? That's waaaay lower than I am comfortable with even if it's true.

As an aside...The engine I am finishing up on this week will be 'broken in' on Redline Racing 50 synthetic. I've seen one of my competitors do it this way with no problems...sooo! The clearances are a bit looser on this engine than I customarily run, but I think will be better considering the engine oil also lubes the gearbox making the heavier oil a necessity. (It's a vintage Mini Cooper)

Rod

 

[swall]

The "How much ZDDP" debate is reminiscent of the "how much lead" debate re preventing valve seat wear.

 

[RossABQ]

From Hemmings News:
Race-based high-performance street engine oil.
Jack Roush, of Roush Fenway Racing, and Valvoline recently combined efforts to bring owners of performance vehicles Roush Motor Oil. Inspired by the race track and formulated for the road, it provides protection for both newer and older performance engines. Sold by the quart for a suggested retail of $7.99 each, the six blends are:
* SAE 5W-20; SAE 5W-30; SAE 5W-50: (API SM)
Fully synthetic engineered for extreme protection and superior performance. Advanced additive package for maximized horsepower, heat protection, and longer-lasting zinc/phosphorus anti-wear. SAE 5W-50 is the recommended oil for the Roush P-51A Mustang.
* SAE 10W-30 and SAE 10W-40: (API SL)
High zinc for classic high-performance engines, including protection for push-rod and flat tappet applications. Fully synthetic engineered for extreme protection and superior performance. Advanced additive package for maximized horsepower, heat protection, and longer-lasting zinc/phosphorus anti-wear.
* BREAK-IN OIL (SAE 40)
High zinc, conventional formula specifically designed to break-in and dyno high performance engines. Requires no additional additives. Also applicable for use in racing applications.
Older engines, and especially flat tappet or push-rod types, require high levels of zinc/phosphorous for added protection. Valvoline increased the level of zinc for the 10W-30 and 10W-40 grades, and in every grade used special low-volatility zinc, which helps to maintain higher levels of phosphorous in the oil instead of blowing it out through the catalyst. All six blends are now available through select retailers. For more information, visit ROUSH Motor Oil - Full Synthetic.
- By Matthew Litwin

 

[Tmoose]

The best number appears to 1000 - 2000 ppm (0.1 - 0.2%) ZDDP

http://www.hotrod.com/pitstop/hrdp_0702_pitstop_zinc_oil_additive/index.html

What was true in 2006 or 2007 is not necessarily true today

 

[evelrod]

Well, for those still interested...

Using Redline Racing 50...

The Mini engine, 1380cc at 14:1 CR has been running for two days and is, for all intent and purpose, the best we have done in this car. Power is up and pumping pressures are spot on, leak down is less than 3% all cylinders. No smoke, no excessive heat...Looks good. We will see after the first race.
No problems breaking in the rings with a full synthetic racing oil. Learn something new every day, even at my age.

Rod

 

[Tmoose]

What cylinder finishing technique and specs were used, what is the ring face material and brand, and how was it broken in?

Dan T

 

[evelrod]

This was a seasonal rebuild for the Mini. Original bore was done with a torque plate on a Sunnen wet hone. Rebuild was hand finished just to break the glaze. New pistons were JE forged flat tops with Deves low tension rings. 73.5mm bore and end gap set at 0.011". Cam lubed with Isky cam lube. Piston skirt clearance is 0.0015" to 0.002". Lubed with Redline 50 Racing synthetic on assembly.

Start up was initially to 1500 rpm to check for, well, just to check everything. Run up to 3000 for initial warm up and then from 3000 to 5000 for about ten minutes. Initial dyno time...warm up as above and initial pull to 6000 to double check jetting, timing, whatever and then a couple of full power pulls to 7800 rpm (limited). Power was good as was everything else (knock wood)! These little BMC A series five port, three main engines are not exactly state of the art, but this one has been pretty good over the last two seasons. This particular engine is ~115 hp at the wheels.
This is for VARA vintage racing and even at that, the engine makes more power than we could get back in the 60's.

No problems, no smoke, no overheat, pumping pressure was
215-240-240-220 (Scatter pattern cam, #'s 1 and 4 have a different camshaft profile from 2 and 3) Leak down was <3% all four cylinders, checked after cool down.

Looks like I'll be using synthetic for break in from now on. Wish I could have found this a little sooner. I'm well into the twilight of my racing career...a few more year, maybe?

Rod

 

[Tmoose]

I was snooping around

http://www.deves.com/tips.cfm

to see what the ring facing options might be, and twice they say "Avoid synthetic oils; they won't allow the rings to seat." Although the process described seems to be a something for everyone combination of re-ring (with ridge reamer) and new build

http://www.deves.com/faq.cfm

"Deves doesn't use anything other than a cast iron alloy for its compression rings. It's a little more flexible than cast iron and not as flexible as some of the other materials that are out there. We don't use chrome plating because it's much harder on the cylinder. Chrome plated rings are also more difficult to seat. The only time Deves has a chrome plated or coated ring is when the OEM manufacturer specifies it."

 

[dgallup]

"These tips have been gathered over the decades that Deves has been producing rings."

In other words, obsolete.

 

[evelrod]

Yes, the cautionary notation about synthetic oil is in the instruction sheet that comes with each set. I've been using Deves since 1980 and this is the first time with a synthetic assembly oil for me.
Still, it has worked just fine and I will probably use the same procedure the next engine as well.
As to the soft iron rings...this is a race engine that will get the usual break in as I described. When we take it to the track it will be given a couple laps to make sure something doesn't fall off and then...RACE TIME!!!
I try to change bearings every five race weekends (they are usually still ok) and rings every two seasons or ten race weekends whichever comes first.
To date, this latest rebuild is the third ring change and the first piston and rod change since 2004. Still no big wear on the cylinders requiring anything other than a clean up hone.
The biggest maintenance on the engine is keeping the valve finish up to my < 5% leakdown standard. Requires lapping the valves at least once a season and a complete valve job once every couple years.

Something of a time honored memory...A long time ago and in a place far, far away....Not really, it was in the early 70's and it was in Socal...A couple guys I worked with, Paul and Silas Pitman (twins) that race supercharged gassers, Paul did very well in funnycar as did his other brother KS from back east. Anyway, I was over to give Silas a hand in putting his 391 Hemi together and I watched him use jewelers rouge on the rings as he punched them in. Question (obviously) "Silas, what the heck are ya doin' there"? "Makes the rings break in quicker", says he!!!
Now, boys and girls, that is just not something I am comfortable doing...Then again, I don't drag race, either.

Rod

 

[Tmoose]

I'm not disputing that almost any engine can be broken in on synthetic oil. I'm fond of short bursts of heavy load for "running in" most components.

Page 54 here.

http://www.bardenbearings.com/PDF CD/MACHINET.PDF

In that case the process is not so much breaking in the mechanical parts, but the distribution of the fancy grease within the high speed bearing that is absolutely necessary to keep heat generation remarkably low during operation. Running a brand new truly high speed grease lubed spindle without proper run in will trigger thermal runaway that can turn the bearings into stinking junk in less than a minute. But after run in the housing may never be more than barely warm to the touch.

I would have been interested in your cylinder walls' surface finish, roundness and taper

Iron non-faced rings are notoriously easy to "break in".
I'm thinking your engine's ring combo may be relatively more likely to seat well than some others. Speed Pro and TRW used to say the thin rails of iron exposed on most moly faced rings would ensure their quick seating. And that the rings were lapped during mfg to be pre-broken in, (visible on a new ring). Sounds like it is the cylinder that "breaks in" after all. Since Mahle bought them all up the tech info is getting danged hard to find. I'm quite nervous.

Here's some semi-vintage ring tech stuff with numbers.

http://www.aa1car.com/library/ring_info_speedpro.pdf

"Hone to finish size with 280 or 400 grit stones. When using an automatic hone such as the CK-10, rough sizing is done with 70 grit stones to within .003" of finished size. intermediate hone with 220 grit stones to within .0005" and finish to size with 280 or 400 grit stones.400 and 600 grit stones are available for both hand operated and automatic equipment, with the 400 grit working out
quite well when a smoother surface is desired. The 600 grit produces a very high polish which is the maximum
smoothness in cylinder wall finishing. Honing with the 600 grit becomes more critical due to the tendency to burnish
and pick up scratches - more prevalent as the surface smoothes out and the crosshatch pattern begins to disappear.
A highly burnished surface can be detrimental, resulting in non-uniform oil film distribution and slow
ring seating due to the slick surface.
Some people have the idea that a given manufacturer's No.500 stone is also 500 grit. Although it is true "the higher the number, the finer the grit”, No. 500 is actually 280 grit, 300 is 220 grit, 200 is 150 grit and 100 is 70 grit. A good honing stone to use is a 280 grit for chrome top rings and 280 or 400 grit for moly top rings. If you are using hand operated equipment, the drill speed should be between 200 to 450 R.P.M. Saturate each cylinder wall and the honing stones with a good grade of honing oil. Kerosene, mineral spirits or a light bodied mineral oil can be used.

 

[evelrod]

TMoose:

I'm not disputing that almost any engine can be broken in on synthetic oil. I'm fond of short bursts of heavy load for "running in" most components.

Well, you have come to the right place!!!

I measured the cylinders and they were all equal (at least as far as my measuring tools go). Bores are still round (tq plate is a wonderful tool) and have taper ranging from 0.0005" to 0.0006"---Now, by anybodies standards that is remarkable considering the time on the engine. Absolutely no "ridge" at the top of the stroke, just a short run with a 300 Varihone (sp) and I was done. (If your numbers are correct, would that make my old hone 220 grit? I haven't a clue, it's nearly as old as I am---In fact, nearly ALL my tools are as old as I am!). A "race weekend" is usually something like five hours engine time...it varies. I've done two two hour races so those weekends would end up something close to eight hours engine time. Total on this bore job is about 25 weekends plus about six or seven good pulls on the dyno. Not a lot of time by "real" race standards, but this IS vintage and I am anal about Zero Defects. I have reason to be a bit overcautious...if you have seen my incident on You Tube from 2003.
Just type in "vintage Mini crash" and watch me bounce.

Incidentally, my crew chief was a BMW certified tech and he said that he had seen new engines run in with synthetic. All I know is I have always been told not to do it as the rings would not seat (indeed, this is the first time)...I think they may have been a little "overcautious" to CTA???

Rod

 

[evelrod]

Okay...I surrender. After several races, I did the usual freshening of the valves and a comp and leak ck. For the first time in several seasons with this engine, the compression ck was down a few points and the leak down had increased from the usual ~5% to ranging from 5% to 20% and after checking, it is from one cylinder's rings not seating properly. Oddly, this has not altered the hp and tq output on the dyno...The engine is still within norms. ???

That's it...Back to Castrol 20W-50 for break in. I'm really NOT too old to learn! I'm guessing that since it was only one cylinder out of the four that the problem can be traced back to the honing process. Since I did the honing and assembly, mea culpa!

I like to experiment a bit...I like to try things that others say cannot work---and MAKE them work! Didn't happen this time, sorry.

Rod

 

[Tmoose]

I'd think a worsening of the initial leakdown might be more indicative of ring scuffing, or maybe valve seat issues, not rings un-seating. It will be interesting to hear more about what ring/cylinder wall malady that the autopsy revealed.

 

[evelrod]

Tmoose, the leak ck was AFTER I had freshened the valve job. Actually, the leak and comp ck was not all THAT bad before, but since it is the end of the season and first race is a couple months off, I usually 'go through the engine'. This time I got the high leak number on the #4. I did the old fashioned ck, squirted a bit of oil in the #4 and, voila, the comp ck came up 5 psi and the leak went to ~10%...soooo...I am guessing that the rings in 4 have 'scuffed' or galled as you suggest. The engine made it's usual hp and tq on the dyno so it is going to stay together until I see some bigger change post race next season. However, when it gets worse (I'm assuming it will), I'll re ring and use Castrol for break in. Going back to what works and has always worked, I guess.

This does not mean, just because I had a failure that the process is flawed. I still attribute the failure to my lack of proper honing or break in procedure.

Rod