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Old 03-20-2019, 03:15 PM
  #16  
robo_porsche
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Originally Posted by Batteaux
I had exactly the same failure with my 2001 3.4 which was equipped with a baffled sump and an extra scavenge pump as protection against starvation. Following the engine failure at Mosport, It was sent to Jake Raby for a rebuild and after assessing the failure he attributed it not to oil starvation but to breakdown of the oil, under the high stress of track use, leading to loss of viscosity and oil pressure, immediate wear of the con rod bearing and eventual failure of the bearing and the con rod. He actually sent me a graphic detailing the stages, under track use, that lead to failure due to breakdown of the oil leading to loss of viscosity and pressure . He calls it "the snowball effect". I had been sharing the car with my son that day so it was running in two run groups and the oil presumably had the chance to get real hot. So for mine, the identified cause was not starvation but oil breakdown (Motul at the time). The propensity for such failures is why Jake specs Joe Gibbs XP9 oil for track use in his engines.
That sounds a little bit similar to what my mechanic told me. Then it is too much heat during track driving that is the cause? Then it sounds like the cooling isn’t enough. IIRC my mechanic said he had a gt3 engine some years ago that had the same issue.

Except replacing the oil to another brand/type, could extra cooling help? 3rd radiator in the front? Extra oil-cooler?

Robert
Old 03-20-2019, 07:18 PM
  #17  
Byprodriver
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Originally Posted by robo_porsche

That sounds a little bit similar to what my mechanic told me. Then it is too much heat during track driving that is the cause? Then it sounds like the cooling isn’t enough. IIRC my mechanic said he had a gt3 engine some years ago that had the same issue.

Except replacing the oil to another brand/type, could extra cooling help? 3rd radiator in the front? Extra oil-cooler?

Robert
Yes, better mechanic too.
Old 03-20-2019, 11:02 PM
  #18  
DreamCarrera
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Originally Posted by robo_porsche
My 996 c2 2002 engine became junk last autumn during a track day. One of the connecting rods stuck to the crankshaft and totally ruined the engine. I have found a new engine but why do you believe my old engine had this failure?

My old engine seemed to work just fine before the crash and was well maintained.

Robert
How experienced are you at tracking (i.e., how hard were you pushing the car)? Were you running street tires or slicks?

Originally Posted by Cuda911
I disagree. Tons of 996's have tons of track hours with no motor failure.

+1

It's certainly not the best car for heavy track use but it certainly isn't the delicate flower many would have you believe it is either.
Old 03-20-2019, 11:40 PM
  #19  
Mike Murphy
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^^ Well, it’s neither, nor. Sure, plenty of folks track these cars without issues. And they handle great on the track.

But like any street car, you put it on the track without mods, it’s bound to fail sooner than later. Most stock cars just aren’t meant to be used on the track repeatedly.

A real track car tends to have mods, such bigger brakes and ducts, external oil coolers, deep sump oil systems, special wheels and wheel bearings, special oil, etc.

The 996 engine isn’t the best track engine. There are known weak points, too many to list. If you have the money, go ahead and take your chances. There’s a guy that tracked a 996 for a decade with all stock components without any issues. I’m sure it happens all the time. And so do engine failures
Old 03-21-2019, 12:44 AM
  #20  
Cuda911
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True of any car, track modded or not.

Old 03-21-2019, 08:07 AM
  #21  
robo_porsche
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Originally Posted by DreamCarrera
How experienced are you at tracking (i.e., how hard were you pushing the car)? Were you running street tires or slicks?

+1

It's certainly not the best car for heavy track use but it certainly isn't the delicate flower many would have you believe it is either.
I was reving the car a lot but I use street tires (Michelin PS2). I have made about 20 track days with car and motorcycle.

I have heard of other people having issues but that has been valves and bore scoring. Bore scoring is the same problem for most modern Porsches, except gt3 and turbo (it’s the lukasil lining that is the problem I heard). My issue is quite rare I think.

Robert
Old 03-21-2019, 09:58 AM
  #22  
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Originally Posted by robo_porsche


I was reving the car a lot but I use street tires (Michelin PS2). I have made about 20 track days with car and motorcycle.

I have heard of other people having issues but that has been valves and bore scoring. Bore scoring is the same problem for most modern Porsches, except gt3 and turbo (it’s the lukasil lining that is the problem I heard). My issue is quite rare I think.

Robert
I don’t know how rare it is. Do a search and you will find plenty of cases of 996s and Boxsters having oil and temp issues on the track. Loss of oil pressure in long tight handers, high indicated water temps, etc. Not uncommon for oil temps to get to 270-280F on the track, so when folks are already using an engine potentially design compromises with respect to oil protection between cylinders and piston, add in 0W oil and 280F oil, and you can see how oil protection becomes a concern.

I don’t hear a lot about valves with this engine. The air-cooled engines, yes, but not so much with the M96.
Old 03-21-2019, 10:42 AM
  #23  
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My car was purchased by Michelin Research and Development in May, 1998 (March 1998 production) from Brumos Porsche as a tire testing track car at their facility in Spartanburg SC. The second owner purchased it with 42k miles on the odometer in 2012. I purchased it two years ago. It now has 92k. It appears to have the original M96.01 engine. The Level 1 "over-revs" (red line) are maxed at about 3 minutes, so who knows how many minutes it has actually spent at redline. Level 2s are a total of about 3.1 seconds, 50k miles ago.

I tracked it at Road Atlanta last Wednesday. It has always run on street tires, as far as I know.

Brumos did install some mods for Michelin including an X51 baffle, wheel studs, jacking points, roll cage (removed before being sold to second owner), Euro GT3 seats, and probably a couple of things I am forgetting about. I did install the 2 quart deep sump kit before my first track day. It has run Mobile1 15W50 its whole life, until I swapped it for XP9 (10W40). Engine still runs great, but I am sure it will break one day.

I decided what I really want for the track is a Radical SR3. To be honest, my 996 just doesn't have enough power. My lack of skill doesn't help. The group I went out with consisted of two GT3 RS, a Ferrari 458, and myself. Once they got rolling, I could not keep up.
Old 03-21-2019, 11:15 AM
  #24  
cds72911
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Re: “To be honest, my 996 just doesn't have enough power. My lack of skill doesn't help.”

My 2 cents from my short racing career is to improve your driving skill before adding tons of power. Its easy to buy a higher horsepower vehicle, but you’ll never get the most out of it if your driving skills aren’t top flight. I’ve watched too many inexperienced drivers buy fast cars and wreck them. For my money, investing in skill improvement first is the way to go. A skilled driver can do a lot with a “slower” car.
Old 03-21-2019, 11:25 AM
  #25  
Splitting Atoms
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Originally Posted by cds72911
My 2 cents from my short racing career is to improve your driving skill before adding tons of power. Its easy to buy a higher horsepower vehicle, but you’ll never get the most out of it if your driving skills aren’t top flight. I’ve watched too many inexperienced drivers buy fast cars and wreck them. For my money, investing in skill improvement first is the way to go. A skilled driver can do a lot with a “slower” car.
I totally agree. I will be driving with instructors for a while until I can drive my 996 closer to its limit. There will come a day though when I need to step up in car to run with the faster groups.

My instructor demonstrated "skill vs car" to me a couple of track days ago when he took me out on track in a stock Mazda3 2.5 and ran down and passed a Ferrari 458 with a less skilled driver. It was amazing.
Old 03-21-2019, 12:25 PM
  #26  
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Originally Posted by Splitting Atoms
I totally agree. I will be driving with instructors for a while until I can drive my 996 closer to its limit. There will come a day though when I need to step up in car to run with the faster groups.

My instructor demonstrated "skill vs car" to me a couple of track days ago when he took me out on track in a stock Mazda3 2.5 and ran down and passed a Ferrari 458 with a less skilled driver. It was amazing.
Oh I'd love to see the look on the Ferrari drivers face when the Mazda went by!
Old 03-21-2019, 01:26 PM
  #27  
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Originally Posted by 808Bill
Oh I'd love to see the look on the Ferrari drivers face when the Mazda went by!
Happens all the time at track events, so I doubt much surprise. I routinely pass much higher HP cars in my Boxster, and have been passed by (gasp!) Miatas.



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