Block & bore surface geometries & contributing factors to bore scoring in M96/M97 engine | 2 of 4

[@sealcuddl3r]

As a 2008 987 S owner, someone who studied mechanical engineering in school, and a huge car and motorbike nerd, these videos push all my buttons. Big thumbs up!

[@PorscheClubofAmerica]

Glad you are enjoying them. Thanks for the support!

[@rolandsmith2141]

Fascinating and completely addictive….watched the first and made myself late for work because I couldn’t stop watching. Thanks

[@PorscheClubofAmerica]

Need us to write you a note to submit to HR? LOL

[@csmarkham]

Full marks to your post production staff for the text annotations-very helpful!-and the graphics/tables cutaways. The best!

[@johnthornley6168]

great video(s). I like the fact that you're adding notes such as "more on moly in 4 minutes". There is so much info to be garnered from these guys that without your note I would find it easy to miss a detail thinking about what was just said. kudos.

[@PorscheClubofAmerica]

Glad you enjoyed it!

[@the3hrdoption637]

Awesome, I understood that to be the case with the cars in the north suffering more scoring due to lack of lubrication from oil not flowing around and through the skirts

[@stevebennett282]

Feeling very fortunate with my 2006 Boxster S: Cast Pistons? Heck Yes!🎉🥳

[@csmarkham]

This is great info. Sure wish I’d had it when I lost my 997.1 S to bore scoring in ‘16. 167k miles was too soon. I ‘downsized’ to an ‘06 987.1 S Boxster, now w/100k miles and glad to know it has cast iron cylinders from this series. Blackstone Labs has always given my oil a clean bill of health, but I’m still going to switch off a low-Moly oil onto a higher level mix because of this info. Thanks, Vu and PCA!

[@lnengineeringllc]

Porsche does not use any cast iron sleeves in any of their sports car models and hasn't since the 924 which had a cast iron block. Your '06 987.1 Boxster S has the same Lokasil cylinders, but the pistons are cast versus the forged pistons that were used in your 997.1 S engine. Regardless, much less to worry about on your Boxster.

[@johnwilliams727]

Awesome vids, as an engineer its interesting these high end cars dont use a cast iron sleeve.

[@lnengineeringllc]

Automakers figured out many years ago that by ditching the cast iron sleeves the engines have much better thermal and volumetric efficiency which leads to making more horsepower. It so helps to reduce engine weight and size.

[@DeanMerrifield]

At 13:20 of the video you talk about inserting a snippet with Lake Speed talking about top tier and ethanol in fuels, where can I find that? Can you add a link in the summary above?

[@PorscheClubofAmerica]

Good catch! We meant to share that in the description and video. Adding momentarily. Here's a Tech Tactics Live Lake did with us on fuel and fuel additives: kzbin.info/www/bejne/iqKkp3uQib6ah5Y

[@PorscheClubofAmerica]

And here is a more recent Tech Tactics East live stream with Lake and Charles presenting about oil, fuel, and oil analysis: kzbin.info/www/bejne/hZSXhXWAhdhrsLM

[@K1dPhresh1]

These links only show the count down to the video, not the actual video with any content😂. It’s late on a Friday, I know the feeling. Correction: Seems only the second link is showing a 60 second countdown to the intended video but not the video itself. First link is working as intended.

[@PorscheClubofAmerica]

@@K1dPhresh1 Fixed, we hope. Weird, as we shared the "share" link KZbin provides...

[@OneDullMan]

Thank ypu for these highly informative videos

[@PorscheClubofAmerica]

Glad you're learning from them!

[@bullfrogzbodyshop]

Looking at a mint cond 06 cayman s, 23k miles on it. Should i be worried about bore scoring with this car in the future? I appreciate the info!

[@tabatauccelli2246]

Great and informative video, a big thank you

[@PorscheClubofAmerica]

Glad you enjoyed it!

[@24hourgmtchannel64]

As a 1999 996 owner, I've honesty lost passion for the car a year after I bought it but to be honest I settled for this car when I was searching for air cooled SC so admittedly it's my fault. While I love all the air cooled cars the crazy price to own one defies my money common sense so like many I bought a 996 based on price. Just my opinion, you have to really have the passion to own a 996 along with being kicked in the financial balls. While I applaud Charles and Jake for providing solutions for the shit stick Porsche sold to customers from 1998 to 2008, they are getting wealthy from it. $15k plus for sleeving and rebuild makes me want to puke and take a sledge to my 996. Wtf Toyota, you consulted them but couldn't stop them from making the AMC Pacer of 911 engines.

[@jdmimportlogistics]

Doesn't just getting the turbo manual avert a lot of these problems? At $50K+ for a good example though think I'll just get a $1K 944 thrash it, not be freaked out about crashing, and perfect technique

[@ATAR1]

Isn’t a boroscope a fairly intrusive process? Would that be included in a normal PPI? I’m looking at a 2007 base cayman… maybe I can offer to pay for an oil change and get the oil analyzed?

[@chrispig7748]

Are 2.7 engines prone to this? I had a 2007 Boxster and it was fine as far as I could tell

[@M_IkeLeBlanc]

Rocket Science in your car. 👍

[@Killer91109]

Thank you for the quality information!

[@PorscheClubofAmerica]

You bet!

[@davedovala2700]

So pretty much hard stop on bore scoring at 2008? I have a 2010 Boxster 3.4 9A1 which I believe has forged pistons. I am cautious about warm up and oil changes for fear of bore scoring.

[@PorscheClubofAmerica]

Bore scoring can happen to later Boxsters, Caymans, and 911s, but it's muuuuch less common and has a different failure mode. It's not really an issue for those cars compared to the 1999-2008 cars. We'd always recommend driving off soon after starting a car to warm it up, but staying out of high revs and full throttle until coolant is up to temp at the least. As for oil changes, stay tuned to the next episode for advice on that, but again, your 987.2 may have different needs compared to the cars profiled in this video series.

[@memememine1]

@@PorscheClubofAmerica Would be awesome if you could elaborate slightly on the failure mode of these later 9a1 type engines.

[@K1dPhresh1]

@@PorscheClubofAmerica until the OIL is up to temp, at least in the 997.1. You could’ve been talking about the 9A1 engines, in which case I don’t know and defer.

[@PorscheClubofAmerica]

@@memememine1 We'll let the experts explain sometime soon... Good question, but don't want to spread bad info.

[@PorscheClubofAmerica]

@@K1dPhresh1 Boxsters and Caymans don't have oil temp gauges, which is why we said at least until the coolant is up to temp... Probably better to run them for a few minutes after coolant is up to temp before full throttle. Edit: @K1dPhresh1 pointed out that the 996s and 997s have an oil temp display in their five-gauge clusters, and the rest of this comment has been corrected.

[@gorporpio]

Sluice box cylinders

[@krassimirpetrov7131]

We need moly ? Maybe I should go back to rotella T6

[@lnengineeringllc]

Diesel oils by default do not have any moly in them and if they do, it's in trace amounts, no more than a standard A40 approved oil. Driven's DT40 and Millers Nano 5w40 are two examples of oils with healthy amounts of moly.

[@1274anil]

I guess I got lucky by saving some money getting gas at Costco as in my area they are all Top Tier. Watching this to help with maintaining my 987.2.

[@krassimirpetrov7131]

Same 987.2 S now after having a 987.1 that had issues. I use QT that was top tier before now they just call it something else . Prob should use shell

[@j.p.2393]

All what Loqui Molly oil has the most Molly in it. Driven oil they mention is way more expensive.

[@DeanMerrifield]

I also disagree with the comment regarding vacuum leaks causing the system to run rich (permanently). The purpose of fuel trim is to allow the ECM to compensate via A/F monitor data for lean or rich mixture conditions within reason. For example excess air (a vacuum leak), or excess fuel (a stuck injector) is picked up by the A/F monitor before the catalyst as a corresponding lean or rich mixture and "trims" the fuel by changing the injector pulse width to achieve a stoichiometric A/F ratio, thereby allowing the vehicle to run without issue. There are limits to the short and long fuel trim allowances but within reason the system can compensate for a lean or rich mixture. Monitoring fuel trim that is out of the normal range for a given vehicle is the technique to identify a problem with non-monitored air or fuel flow but it doesn't necessarily mean the combustion mixture is lean or rich.

[@K1dPhresh1]

So if un-metered air is getting into the engine it will compensate, yes? And if that un-metered air doesn’t get fixed it will continue to compensate thus dumping in more fuel and washing down the bores. At least that’s how I understand it.

[@DeanMerrifield]

@@K1dPhresh1 If unmetered air is entering the system, that is excess air. You need continuous excess fuel to mix with that excess air to bring the mixture back to stoichiometric. The A/F sensor forces that through fuel trim adjustment. That excess unmetered air (vacuum leak) allows the vehicle to operate with less throttle opening to achieve the same engine rpm under load. Eventually when the leak becomes too great the throttle position sensor, MAF and fuel trim are out of sync (beyond the ECM limits) and the MIL will light. With a small vacuum leak the combustion remains stoichiometric, but at a lesser throttle opening.

[@K1dPhresh1]

@@DeanMerrifield so then if you had a throttle cable operated vehicle it would be more of a concern since the ECM is taken out of the equation as for as throttle controls are concerned and THEN you’d have a concern? Have you watched the video he’s referring to with Tony Callus? It seemed to make all the sense in the world to me then. You’ve got me wondering now. I guess I need to go rewatch it now.

[@DeanMerrifield]

@@K1dPhresh1 Consider that the ECM will trim the fuel, in a unmetered air event or vacuum leak, by adding more fuel. This additional fuel simply brings the mixture from a lean condition (excess air) to a stoichiometric condition optimal for combustion. The A/F sensor data is within spec but the fuel trim is rich. There's no excess fuel only that amount added to compensate for the vacuum leak. The results is less throttle being used for a given engine load as the vacuum leak bypasses the throttle and MAF. A more likely condition for cylinder wash down is a dirty or stuck injector, in that case the ECM reduces injector pulse width, reducing fuel across all injectors. This results is lean cylinders with working injectors and rich cylinders with faulty injectors, the A/F sensor reads the aggregate combustion output which is within spec but the fuel trim is lean.

[@K1dPhresh1]

@@DeanMerrifield so you don’t see vacuum leaks as a concern as far as bore scoring is concerned then? In my UOA I had a higher fuel dilution than expected. I smoked the vehicle and found zero vacuum leaks. I replaced the fuel injectors which I found were original to the car. Waiting on my next oil change to see if the fuel dilution comes down. But then there is also some talk that was once believe to be higher than usual fuel dilution may be closer to what is expected than not. My fuel dilution was trending upward after the two oil changes during my ownership, so not that much trend data to look at.

[@EhWassAmattaU]

I disagree with the paint can / mass theory. You forgot about the substance between them. Coolant, that is constantly circulating and not going above 220f. The theory sounds good, but I don't think that paint can theory holds water...