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ZDDP again

ZDDP again

ZDDP again

(OP)
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  

RE: ZDDP again

for the equipment you mention i would not use supplementary additives as long as oils with the required quality are readily available. the ZDDP additives sold through consumerchannels contain usually more then 90% cheap base oil as a carrier and less then 10% actual additive - the carrier oil is needed to make sure it dissolves well when added to the oil to be "upgraded". there are two drawbacks with these additives: they are rather expensive and it is hard to tell whether they will be effective or not. the additive industry supplies a lot of different zinc/sulphur compounds aimed at various end products and various operating temperatures and with the consumer type products you will never know what you actually get. i therefore would stick to standard completely formulated oils of say the highest API quality that is not restrained in metallic additive content, like API SG or SF. Those oils will still be available for quite a long time and will contain the "classic" type of zinc-additives, since these are far cheaper then newly developed additves that can be classified as "lowSAPS". i therefore see no need for worry for flat tapped engines, since oils for that type of engine will problably around for another 10 years or so - and by then the additive industry problably has come up with even more capable "lowSAPS" alternatives.  
 

RE: ZDDP again

Sorry to thread hi-jack but it's related.

I'm wondering about the suitability of high zinc oils for engine break-in.  I know it's better for the valve train and high-contact pressure areas but is the ring/cylinder break-in improved or not?

I'm looking for a second opinion to back up or dispute what my resident engine expert is telling me.  Thanks.

RE: ZDDP again

ring cilinder break in is usually best and fastest accomplished with the oil the engine came with when new. most manufacturers use a proprietary running in oil that has been specially formulated to aid in running in and also provide the necessary extra cooling capability that is needed when running in still relatively rough surfaces. the latter is accomplished by using a slightly thinner oil then later would be advised for a given ambient temperature. the best thing you can do is use that engine oil for the full period it is advised by the manufacturer and gradually increase the load of the engine. there is an enormous variety in qualities used by various manufacturers, ranging from API SE-SM and API CF-CJ-4.

generally speaking you might say that they use the least amount of zinc possible to speed up the running in process, but still enough to withstand the loading in the valvetrain and the use as an antioxidant for the foreseen period.

if you are reconditioning engines yourself you can take the above as a guide - use the standard prescribed oil quality, perhaps one SAE grade thinner then is to be used later and gradually increase the load over time (if possible).

since drainintervals have gone up quite considerably over the last 20 years there is much less difference between service oils and running in oils then there used to be, also due to better manufacturing practices and materials the running in proces is far less critical nowadays then it used to be.

RE: ZDDP again

(OP)
Interesting.  I've been told by folks that "should" know what they are about, that the many new cars come with the 'regular' recommended oil grade as initial, so called, break in oil. From what I have observed, that is likely something like a 5W-20 synthetic.

This much I do know for fact, the last two race engines I built last year  (and the Lotus twincam I'm building now) have been run in on Castrol 20W-50 for the first warm up, about a half hour to an hour run in and tune up time.  I then drain the entire system, accumulator, sump, heat exchanger and, the AN -10 lines, change the filter and, replace the lube with Redline synthetic race oil for all subsequent tune and dyno runs.  To date, I have had ZERO problems...no unusual smoking or oil consumption problems and no unusual wear problems with flat tappets or DOHC.

Incidentally, I save the 'run in oil' and use it in my diesel truck...

Rod   

RE: ZDDP again

I have yet to see a manufacturer recommended run-in oil for these engines and our oil supplier has no such knowledge either.  We are indeed a remanufacturer so the engines are empty until we fill 'em.  We can control the load rate when new though.  

I did notice that another reputable builder uses "straight low-ash low-detergent 30WT oil", instead of typical 40- or multi-weight, during their break-in process.  No mention of zinc though...I assume by "straight" they mean non-multi-weight but it could be construed in reference to basic or low additive.

Are there any SAE or otherwise testing procedures for break-in testing?  What would you be testing to be able to say an engine was broken in well or not?   

RE: ZDDP again

I use a cheaper oil for break in as I expect to run it for a short time then change to my regular synthetic oil.

I do this to flush break in and assembly contamination.

Light weight single grade makes sense as it has more slippery stuff and less additive than multi grade. Light weight flushes better.

I think anti scuff is an important characteristic in break in. I am not an expert in this field, but I would expect reasonably high ZDDP content improves anti scuff.

drwebb seems to be the expert on oil formulation. I would be interested in his views on anti scuff additives.

Regards

eng-tips, by professional engineers for professional engineers
Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips Fora.
 

RE: ZDDP again

in my experience european engine builders all have there own way of deciding whether an engine is run in well or not. they usually have tested various oils and dismantled the engines after a given amount of time and on the basis of those results opted for a proprietary formulation. in the past those oils usually were rather cheap single weight oils that needed to be changed somewhere between 5000 and 15000 km after the engine was put in use. since nowadays drain intervals may go up to about 160000 km far better quality oils are used and the viscosity is more in line with what would otherwise be advised.

in the reconditioning industry usually single grade oils are used for a short run in at the reconditioning plant and the engines are then shipped without oil to the enduser. the single grade oil is then usually filtered/centrifuged and used for quite some time in other rebuilt engines. in many plants the oil is seldom changed because they have sufficient top up to keep the quality at the required level.

for engine builders the actual criteria for "good" run in is that they do not get complaints about excessive oil consumption and that the engine reaches a lifespan that is greater then the warranty period. everything that happens after that is of no interest to the engine builder - but can ofcourse be important for the enduser.

i think that nowadays run in with modern engines is far less critical then it used to be - one important point to keep in mind is that, when due to poor run in, the lifespan of the engine is compromised, it will only show up when that point is reached - and that is usually many years after reconditioning.

ofcourse, when you as a reconditioner, get many complaints about excessive oil consumption or excessive valve train wear in the first year after rebuild, you might need to investigate whether there is something wrong with the way the engines are reconditioned, but generally speaking, with modern materials, the proces is not as critical as it used to be.

RE: ZDDP again

Romke, you confirmed exactly my thoughts and intentions.

RE: ZDDP again

I suspect properties of supposedly special 'break-in oils' have more to do with cost than performance.  The requirements (especially detergency and anti-oxicancy) for crankcase oil that only has to last 1 min.-600 miles are pretty mild, and cost savings can be significant when it is bought in bulk.  Consider that many of the Sequence Tests for oil performance specify new test engines be run in on the same oil being tested for approval for service fill.

As for ZDDP, the new engine oil categories still require passing a Sequence IVA test for cam wear protection regardless of the chemistry used, and the SM requirements are more stringent than previous SL category.  This makes the worry in the field over chemistry sound to me reminiscent of the changeover from leaded- to low-lead and unleaded gas.  If someone believes they need more ZDDP then any top treat will need to raise the P level of the oil from whatever it is to ca. 0.10-0.14%.  Most top treat oils won't disclose their level of P, leading me to concur they are formulated to deliver more 'peace of mind' to their customers than active ingredients.

RE: ZDDP again

dr webb

you are right that cost is very important when you only use the oil for a short period, as is usually the case in a reconditioning plant. european truckbuilders however now run their engines for a period of up to several hours before mounting it in a truck - where the oil may have to last for up to 100.000 miles in actual service.

there are therefore two types of "run in" oil in use - one that merely serves to check whether the engine is tight and meets the specification requirements and another type that after that test also has to perform in actual service for quite a while. the first type is very costeffective, the second is more likely a ful blown heavy duty diesel engine oil. the same applies to gasoline engines, although in europe nowadays only full spec gasoline engine oils are used.

it seems that the term run in oil nowadays means something different then it used to be, a better term would be initial fill oil for the engine builder and a "pure" run in oil for the reconditioner. the latter would have to last only a short term and therefore has to meet far less stringent specifications.

RE: ZDDP again

For new or rebuilt engines, why not fill with the full syn. oil you're going to run?  Break in engine, change filter, done.

Gold is for the mistress - silver for the maid
Copper for the craftsman cunning in his trade.
"Good!" said the Baron, sitting in his hall
But iron - cold iron is the master of them all.
Rudyard Kipling
 

RE: ZDDP again

(OP)
Since I am heavily involved in the vintage car market and am actively campaigning two vintage race cars as well as several vintage/antique vehicles, it comes as no surprise that purveyors of 'vintage' auto parts would inundate me with offers of all sort of 'snake oil'.  The most recent offer was today from Moss Motors (definitely the best British car parts stores in the U.S.) is now selling a "vintage oil" with all the 'old formula' anti wear...read that ZDDP...for $5.95/qt.  They also offer a small bottle of the additive itself for $9.95/bottle.  I am not likely to ever avail myself of this offer, but I'll just betcha they will sell a 'ton' of it!

Rod

RE: ZDDP again

They better sell it quick, I heard that either Quaker State or Pennzoil has figured out they can sell the same oil they used to price at 99 cents/qt, for $5 a qt, and is rolling out a "vintage" blend.  Can't remember which of the two it was.

RE: ZDDP again

In defense of QS/Pennzoil (to whom I have no affiliation), there may be no motor oils that can still be sold for $0.99/qt as the price of the base oils alone are at or above $4/gallon.  Add to that the big additive companies charge a premium to marketers for keeping 'obsolete' spec ingredients in their portfolios.  Those who desire the 'peace of mind' of the 'good old oil' will have to pay a premium for the now 'specialty' products . . .

RE: ZDDP again

(OP)
Moss's newest addition, the engine oil at %5.95/qt is not listed on their site, yet.  However, the ZDDP additive is.

ZDDPlus additive   www.mossmotors.com

I would guess it will sell as easily as the "oil for engines over 75,000 miles".

Rod  

RE: ZDDP again

... or the oils "specially formulated for 4x4's"

 

RE: ZDDP again

I always wondered how the engine knew it was installed in a 4X4.

Regards

eng-tips, by professional engineers for professional engineers
Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips Fora.
 

RE: ZDDP again

I was reading some tribology book at the UMass Lowell Library. My notes are elsewhere.  A section mentioned some investigation determining there being an optimum level of ZXXX to form and sustain the best wear resistant film.
Maybe 1% being optimum, and way better than 2% ??

RE: ZDDP again

I have been trying to keep up with this topic and trying to make an educated choice on break in oils for strickly aircooled VW race engines. From what I have read so far, many manufacturers  are reducing the ZDDP levels and, as a result, many flat tappet cams are wearing and going flat within the break in period (V8 world included). Castrol is the only company so far that I know of that has acknowleged this and is supposed to be researching the claims. I think it would be fair to suspect the higher spring rates and seat pressures many engines are now running. Some solutions are hard weld camshafts that are copper coated and parkerized or SLR treated lifters to extend camshaft / lifter life. I realize that during most break in proceedures, double or triple springs are removed to prevent unnecessary wear, but cams and lifters are still wearing to the point of replacement. This topic is out of my primary daily endeavors, maybe someone else here could better explain if the reduction in additives are truely the culprit.      

RE: ZDDP again

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.

RE: ZDDP again

(OP)
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
 

RE: ZDDP again

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

RE: ZDDP again

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

RE: ZDDP again

(OP)
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

RE: ZDDP again

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

Dan T

RE: ZDDP again

(OP)
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
 
 

RE: ZDDP again

I was snooping around 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."

RE: ZDDP again

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

In other words, obsolete.

RE: ZDDP again

(OP)
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

 

RE: ZDDP again

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%20CD/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.

RE: ZDDP again

(OP)
TMoose:

Quote:

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

RE: ZDDP again

(OP)
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

RE: ZDDP again

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.

RE: ZDDP again

(OP)
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

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