jgiannone

I know I'll end up regretting this, but I'll do it anyway. With all the talk, threads, and experience around 996's in particular, and engine longevity in general, I thought this might be helpful. For background, I have a 996 that I've races in PCA for ten years now. When I bought the car, it was a used street car with roughly 40,000 miles on the odometer. Since then, it was converted to a full race car, first to run in "I Stock", and for the last seven years as a GTB1. The IMS bearing was upgraded right away, but modifications to the engine have been limited per the GTB1 rules: headers, air intake, DME reprogram, under drive pulley, lightweight flywheel. All of the engine internals are stock as built at the factory. Nothing has been opened up. Now, at 66,000 miles, the engine still runs strong with modest compression loss and leak down. 26,000 race miles, or roughly 260 hours at race pace.

To reiterate what many have said, engine oil changes occur after every 6 to 9 race days (2 or 3 events). I have used only one oil during the entire time I've owned the car, Mobil 1 15-50. For those who disregard Mobil 1 because of its lack of ZDDP, the 15-50 bottle clearly states an upgraded to the ZDDP concentration, and I always assumed the extra weight would help with high ambient summer heat and race conditions. Rarely does the car get started in sub freezing temperatures. I can count on one hand the number of over revs during the ten years; 3 were rev limiters being hit, and two were "5 to 2" downshifts. Those were the ones that scared me, one being 8800 revs; the other being 9200 revs. I thought for sure that would have killed it, but those were four years ago at VIR.

In my opinion, the things that kill engines are 1) thermal shock, and 2) mechanical shock. I always warm the engine up before I go out on track. I allow at least ten, if not 15 minutes of normal idle to allow the water temperate to reach 180 degrees, or normal operating temp before i start to hammer it. It always amazes me how people can start a cold car, and immediately go out on track with their foot to the floor. Think about all those issues with cracked cylinders and heads, where the water temperature in the water jacket may be 30/40/50 degrees, and the cylinder/head temp spikes to 1000 degrees. The engine oil will follow the water temp up, so it takes a while for oil temp to get to a normal operating temp, back to the point of limiting full throttle until maybe 200 degrees on the oil.

As to the mechanical shock, there's a reason why so many car parts fail at Sebring. The bumps tear everything apart from the wheels, to the wheel bearings, to the axles, to the trans, to the crank, to the chain tensors, etc etc. Parts that were meant to operate at "X" level of accelerations, measured in G's, and being subjected to much higher G loading during those shock events. Shifting the car too fast creates the same excessive G loads. Slam shifting the gears not only stresses the gearbox and synchs, but puts undue stress into many other engine components. The engine was designed to take a certain amount of time to decelerate from 7000 RPM's to 5800 RPM's, and if you force it to do that in a fraction of the normal time, the G loads spike on all of those parts. These are reasons why all the newer race cars, with lightning fast sequential shifters, have and need very sophisticated engine management software, otherwise the engines with self destruct.

Again, I've been very lucky. 26000 race miles on a stock 996 engine. But I've used a few "best practices" when it comes to operation and maintenance. In summary, let the car warm up, take it easy at first, change the oil regularly and watch the shock loading. Like I said at the start, I hope end regretting this, meaning, I hope the next time I start my car, it doesn't explode. I do know, at some point, nothing lasts for ever. But for now, still running strong.

JSETarga

Making me more optimistic about my build! Thank you for sharing your positive experience.

jllphan

A great datapoint to add to the community, thanks for sharing.

I’ve always thought of Porsche as a company that builds very robust and durable sports cars. I believe the 996 is exactly that. They are not perfect; any car built with performance over dependability is subject to failure based on the tolerances with which they are built. But with proper (preventative) maintenance and an owner that pays attention, I feel these cars are as reliable as any 911 built before or after simply due to the fact that all 911’s from any era have their week points. The forum is designed to help those with issues more than celebrating what hasn’t gone wrong given most experiencing the latter have no reason to come here and post. So all the issues you read online are the exception and not the rule.

I’ve driven my C4s a lot more than normal over the past few days and turned 110k mi yesterday. It’s amazing to think a car built to such tolerances are able to rack up the miles with no need to be opened up... ask anyone with a Ferrari or Lambo to do the same and they will laugh you out of the room.

Coopduc

Congrats.
Nothing to regret, you have a system, you are sticking to it, and it is working for you. Keep up the good work. Even if it blows up tomorrow you have gotten great performance and enjoyment out of the car!
Key take-aways for the “rest of us”:
1. Maintain it
2. Warm it up
3. Drive it like you stole it
4. Repeat often!

Porschetech3

Thanks for sharing!! I always enjoy hearing from owners who put their cars to the test on the track. 26k miles of track pace is also what I have seen with the fleet of 100 Porsche Driving School cars that I had to maintain. They also used Mobil 1 A40 exclusively ( due to contract requirements) and warranty purposes. 0-40 Mobil 1 Euro until the 5w-50 FS-2 was released, now that;s all they use.No special warm up ritual, they would just start up how ever many cars they would need for the amount of students, let them idle warm up while the students were saddling up. Those "students" were not the best drivers, they drove the cars hard, missed gears, over-reved, burned up clutches ect., but the engines held up.

Prelude Guy

It's great to hear your engine has lasted and that you have been able to completely enjoy it!

If there is one take-away from your story, it is that the M96 reliability is literally across the whole spectrum. From an engine blowing up while idling at a stop light to lasting hard long-term tracking abuse. Don't sink money into making the engine more "reliable". It will never happen. Just enjoy it while it is still running!

Byprodriver

Yeah why bother changing the oil or filter? It will just get dirty again!

Porschetech3

I remember when synthetic oil first came out, it was claimed to "never need changing". Calera Police Dept. fell for the hype, they ran a 460 Police Interceptor of 50k before the engine failed..lol

NYoutftr

JGIANNONE

In my opinion, the things that kill engines are 1) thermal shock, and 2) mechanical shock. I always warm the engine up before I go out on track. I allow at least ten, if not 15 minutes of normal idle to allow the water temperate to reach 180 degrees, or normal operating temp before i start to hammer it.


Nice write up.
I especially paid attention to your statement, the your ritual of starting and letting run for 15 minutes or so.
I have always started all of my vehicles and let them idle a little bit before driving, (Upstate NY has huge variations in temps, not like the South)
In the past I along with other 996 owners have been, let's say, not agreed with about this.
There are threads here with the Porsche experts claiming, get in start it and drive it.
I do understand the factual argument about fuel residual going into oil from prolonged idling, it was just good to hear the other side of the discussion.
Thanks again
David

reaper1

1) Curious on your opinion of an oil pan upgrade and did this car have one?

2) What's your opinion on running a performance tune for track duty and did you ever run one?

​​​​​​Thanks

NuttyProfessor

You're thread is very intriguing and may prove a point that our Porsches love to be driven hard instead of being parked most of the time. If you don't mind, please share with the forum a little more about your car and how you maintained it.

What year model? You say you've owned the car for 10 years and have modest performance upgrades per track rules, but do you know the age of the engine? Is it the original engine or an "AT" factory replacement? What IMS bearing did you chose to install? Has the engine every been rebuilt in your 10 years of ownership? What preventive maintenance? AOS? Water pump? Chain guides? etc. Since cylinder bore scoring has become a serious concern among M96 owners, have you thought about having the cylinders scoped as a precaution? If so, in light of the annual track use, how was the health of the bores? Not speaking of compression, but any signs of scoring?

Please forgive all the questions, but when I see a thread started like this, I want to know more. We can all learn from you and your experience with this car.

Thank you!

AnthonyGS

I prefer to warm my cars up by driving them like I’m “driving miss daisy.” Then once unto normal operating temperature and oil pressure has dropped to a warm pressure, I let her rip. I pretty much drive like I stole it unless conditions don’t allow it. I drive a bit more friendly when I have passengers. Most passengers don’t like quick turns.....

turbogrill

What about oil starvation? Have you had any issues with that?

jgiannone

In no particular order....Im aware of the argument about not letting a car idle for too long, but I happen to believe that most of that dates back to the days of carburetors and less than perfect cylinder sealing. With modern fuel injection, better sealing, AND, changing the oil every 6-9 days, whatever dilution occurs is offset by limiting the thermal shock (temps changing too fast). The car is a 2003, and the engine is the original engine, with original engine number. As I said earlier, no rebuilds. Yes, the water pump has been replaced twice, the IMS once with which one I don't know, For all race/track use, I had a Motorsport Air Oil Separator installed. This is an absolute must. The OEM just isn't up to track usage, and will fail early on. When they fail, at best you get the tell tale oil smoke out the back upon start up; at worst, you get a nuclear mushroom cloud where a quart of oil gets ingested and burned (hydrolock pressures are the concern). The motorsport part is like $750 vs $150 for the OEM, but is works.

It has a Brey Kraus deep sump oil kit, and I run the oil at the top fill mark all the time. Occasionally, if I overfill by a 1/4 of a quart or more, I'll get a little ingestion back through the mass air sensor which will make the car run rough until it cleans itself out.

All the normal maintenance items like air filters, plugs, coils are changed on a schedule.

I have to believe, even 20years ago at the infancy of these cars, that the Porsche engineers new that they would sell a million of these things, and all over the world, guys would run then like they;re on the autobahn, and, they didn't want half of them coming back under warranty. But, the "German" idea of maintenance and procedures may be different than a world-view lowest common denominator approach. Yes they royally F'd up the IMS issue, and the rear main seal issue is an annoyance, but the cars don't don't fail because of it.

I recall BMW engines having oiling and bearing issues. The same thing. Go out on a freezing cold day, start the car and IMMEDIATELY hammer it. The older M3's, and even the newer M%'s and M6's all had these bearing issues. Imagine that, BMW's flagship cars having a design flaw, or, poor judgement/practice/intent.

I've raced around people for years. I watch some less-experienced drivers make all sorts of time losing mistakes, only to try to make it up by slam shifting the car on the straights. And I've seen countless cracked rods, pistons, cranks, chain rail failures. To repeat; warm up slowly (any good athlete would say so), change oil frequently, avoid overrevs, avoid shock loading. I think we'll get what those original Porsche engineers wanted.

JTT

Remember that he is at the track, so idling warm up is really the only way. When Jake is talking about starting and driving away, it's gently driving on the street (driving Miss Daisy form), not heading straight out onto the track, foot to the floor. I've always had concerns about warming for track days myself. I'm not at all comfortable flogging on a cold car (big throttle openings and/or high revs), but at the track you're often forced to unless you have time before your session to idle. Doing laps of the pits is generally frowned upon