Pioneer stepped up for me

[bernieb1]

Pioneer Centres (Daniel in service and out own Chris Huck) have been 100% supportive following my recent engine failure on 2000 Boxster S recently out of warranty. Daniel worked with Porsche to replace the motor as "goodwill". This has been a very consistent pattern with Shawn and Daniel with any reasonable requests. Having purchased my Porsches there and having all service there likely helps of course.

[MikeD]

Sweet! Glad to hear that Bernie. I've been more than a little nervous about my Boxster since witnessing what happened to yours. It's nice to hear Porsche isn't just conceerned about the bottom line and still cares about their customers.

[Tim Comeau]

I'm surprised Daniel is still alive. He works so hard and so long every day, you'd think he'd a had a heart attack long ago! He's good people.

[paul-silver]

Yikes! What happened to your Boxster that it needed a new engine? The reason I ask is I have a an 02 BoxS, and want to
be able to avoid such things...

Paul

[MikeD]

I was just going to ask the same question Paul.

Bernie, please let us know what Pioneer says caused the shavings. Thanks.

[bernieb1]

there wasn't any dissassembly done here, motor just packed off to Porsche and no feedback is anticipated. Steve Grosskemper raised the possibility of "spun rod bearing" from oil starvation, Scott Slauson at PCA tech section suggested possible "failed rear intermediate shaft bearing." I haven't picked up any clear things to prevent failure, hopefully it was just a vulnerable engine. I asked about conversion to a dry sump system but Steve G said that what's available in the aftermarket isn't a true complete dry sump system and I think is pricey. A Brey-Krause oil sump pan that increases capacity by .5 qts and adjusts baffling is available but of unknown effectiveness. I'm sure open to any thoughts and ideas.

[MikeD]

I was chatting with Tim @ Mind Over earlier today. The info he had was that the Boxster (and I suspect 996) motors, when tracked, need to be completely full of oil. Not over-full as that will potentially cause RMS failure, but full. The motor will go through about half a quart of oil for every 80 minutes of track time. So it should be checked and topped off after every run session. Even half a quart down can begin to cause problems.

I know that I am going to be keeping a LOT closer eye on my oil level from now on. I'm also going to be getting it changed a lot more frequently.

[David J Marguglio]

As you can imagine, there are volumes of discussion on the spec-944 race forum regarding spun rod bearings (well really just #2) and the efficacy of various solutions (oil levels/types, baffling, accusump, etc.). In 20+ years of racing 944's they have reached no consensus. I suspect that issue would have been resolved if Porsche had supported 944 in competition (PMS). I see a similar pattern with Boxsters. Okay, (headgear on) go ahead and start pelting me with the stones, but I feel the empirical evidence speaks for itself. In the interim, if you are concerned about oil as the culprit for failures, I suggest you look into racing oil as it tends to maintain closer to constant pressure under race conditions.

[MikeD]

Please tell me more about said "racing oil".

[Tim Comeau]

I'm with Dave on this one. My "racing oil" is, of course synthetic. And I check it after every 30 minute session or race. With the 944's, we fill it 1/8th inch over the full mark.
The syn oils maintain their viscosity at higher temps better than natural based oils. Natural based oils tend to get thinner and thinner with increased temps so your pressure goes down and the ability of the oil to cling to parts goes down as well. Different syn oil companies add different chemical packages.
The oil I personally use in all my race cars is Liqui-Moly. It has a molybdenum disulphide additive the makes it even more stable under high temps. In April, A Liqui-Moly rep. asked me to give it a try. I've run 8 race weekends, including three 3-Hour enduros, 2 DE events at the stadium, one TT at Willow, a couple AX's this year all on the same Liqui-Moly. I drove the car to almost every event, too! Absolutely no oil pressure or temperature related problems. I'm convinced that this is a great product that DOES what they say it will.
If you want to try some, here's my source.
Inter Auto Parts
5060 Convoy St.
858.279.9900

There is a discount if you tell them you're with PCA!
Talk to Mr. Russo.

At your service,
Tim

[David J Marguglio]

This should probably be moved to the Tech section, but since you asked, I will give it to ya.

The race oils that guys that I know are using are AMSOil, LiquiMoly and Redline. Based on their experience they are far superior to Mobil 1 on the track, but YMMV.

On the issue of rod failures, here are some quotes from a couple of well-respected engine builders.

There has been a great deal of discussion regarding this problem over the years. None of it seems to have helped one bit.

I saw 944's blow up in 1991 when I started racing and I see them blow up now. I hate to just say that the engine is unsuitable for racing, but it seems that that is really the case.

Here is what I know from first hand experience:

Accusumps do nothing.
Cross drilling the rod journals does nothing, and may make it worse.
The oil level is critical.
The hot oil pressure is not particularly important.
Oil/Air separators and crankcase vents do nothing.
There is no correlation whatsoever between fuel mixture distribution and rod bearing failures.

Here is what seems to help:

Keeping Rpm below 6000 rpm
Checking the oil level after EVERY session
Never running enduros
Keeping the oil cool
Keeping the oil pressure as high as possible. The racer's only means of doing this is by cooling the oil.
Modifying the oil pan so the effective oil level in corners is higher.

Here are some ways that a 911 differs from a 944. This is relevant because 911's just don't have oil related bearing failures.

911s have a simple but effective dry sump system.
911s have a very large pressure pump. They almost never run short of volume.
911s don't have an aerodynamic mess in the crankcase.
911s tend to have better control of oil temp
911s have large oil tanks, even when you are three quarts low, there is still plenty of oil.
911s have a very open crankcase breathing system.

_________________
Chris Cervelli
Technodyne Inc.

In 1985, when we won Firehawk Grand Sport, we had to run on Firestone S660 tires. The bottom end of the engine was never disassembled and we never had a bearing failure. At the end of the year, the engine was disassembled and the rod bearings were great. Why? The tires had no stick. Cornering never exceed .96G, we didn't hit curbs, drive off the track, and braking didn't exceed .98G. We shifted at 6400 rpm because the rev limiter cut in at 6500.

Here's why the rod bearing fails. There isn't sufficient oil at the rod bearing to lubricate and cool it. Bearing cooling is one of the most important functions performed by lubricating oil.

Why isn't the oil supply sufficient? There are a number of reasons. The first is the oil pump design and the oil pump supply. The gerotor pump design should never be driven faster than 70% of crankshaft speed. On the 944, it's locked to the crankshaft. At high revs, air can be drawn through the oil in the oil pan when the oil covering the pickup is marginal and enter the oil system. When this air reaches the oil pump, there is an instantaneous loss of oil pressure until the air is compressed. When the air reaches the oil gallery, it is mixed with oil and traveling at quite a velocity. The oil inlet port to the main oil gallery is opposite the oil supply to #1 main bearing. #1 main bearing supplies oil to #1 rod bearing. Oil has considerably greater mass per unit volume than air so oil goes to #1 main bearing and air displaced and forced down the gallery to #2 main bearing supply. #2 main bearing supplies oil to #2 rod bearing. Main bearings can live with marginal lubrication much longer than can rod bearings. Rod bearings fail rapidly when subjected to air and oil mixed. This is the total reason.

What can be done about this?

0. Run tires with no grip
1. The oil pan can be baffled better than the factory baffling to keep the oil level higher at all times.
2. The oil pickup can be modified to reduce the ability for air to enter.
3. Air can be removed from the oil before the air gets to the engine.
4. Bearings can be coated with an oil retaining film that makes the bearings more durable when supplied insufficient oil.
5. Modifications can be done to the oil pan to remove more oil from the crankshaft (may not be legal in PCA) and return this oil to the deep part of the sump.
6. Use an accusump with an anti-backfeed one way valve to keep the instantaneous pressure loss from occurring (I feel this is the least important but OK with the rules makers).
7. Never run the oil level over full as this allows the crankshaft to whip more air into the oil.

The question here is just what is full? Try checking the oil level this way and run it half way between the full and add line. Engine fully up to temperature, remove the dipstick and plug tube with finger. Rev engine to 5000rpm and hold for 15 sec. Switch off engine. Immediately after crank stops turning, insert dipstick and remove, reading level.

Jon Milledge

Hope this helps someone.

[MikeD]

OK. I've heard of Redline, but not the others.

This article is a few years old, but it seems like the advice given might still be applicable.

[url=http://www.pca.org/tech/tech_qa_question.asp?id={361FCF02-7326-4C88-96A5-B5C2CE361057}]996 oilkit / oil pump update[/url]

[kary]

Mike, while the article has some good points it begins very poorly in my opinion. I saw a 996 blow an engine at a TracQuest event at Buttonwillow. I saw a 996, that had been at a number POC events, have anti-freeze in the oil. That engine began to smoke and gradually blew as well. So I an ot sure where his statement comes from but from the limited examples I have seen, it does happen.

[MikeD]

I gave him the benifit of the doubt as the article was dated Aug 2000. At the time I'm sure very few 996 and even 986's had been tracked with consistency for any length of time.

I do agree that since it is so out-of-date the relavancy of the information is suspect.

[MikeD]

I guess I should add, that what I am really looking for is opions on the Porsche Oil Kit. Has anyone added this to their car? Would it make sense to spend the $1300, or will it be a waste of time?