996 Engine Failure and Lessons Learned
11-13-2012, 07:14 PM
#16
Rennlist Member
Thread Starter
That sucks! Sorry to hear your bad experience and thanks for sharing. I think we will never know why and how the engine failed. With all the mods, sounds like the previous owner was fully prepared to push (or did push) the car's limit.
The deep sump mod without the spacer on the pick up tube will be worse than stock oil pick up so making the mod harmful. I think it's very difficult to assess the health of an engine that has seen the tracks. With R-comp tires, these cars can pull quite a bit of g's. So it's possible the car was already on its last legs when you bought it...
Again, sorry for your misfortune.
The deep sump mod without the spacer on the pick up tube will be worse than stock oil pick up so making the mod harmful. I think it's very difficult to assess the health of an engine that has seen the tracks. With R-comp tires, these cars can pull quite a bit of g's. So it's possible the car was already on its last legs when you bought it...
Again, sorry for your misfortune.
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Insaty (07-21-2023)
11-13-2012, 07:28 PM
#17
Burning Brakes
Oil starvation of high G turns (one direction only, I think, though I can't recall which) has been documented for a long time. I re-read this several times, and I am sorry for your financial loss. Many of us fear that same loss. You car may have failed on the street, the exact same way, regardless...you will never know.
The X51 modification, with 2 extra pick up points, is to me, the basics required to prevent this starvation, or more inexpensively, an Accusump, that maintains the oil pressure from an external pressurized reservoir. I don't track, but as an engineer, it's not hard to see where improvements for track use would be helpful, both in lubrication and cooling. No pick up extension on a deep sump is worse than no deep sump at all, due to the pick up being closer to the foaming level during a turn, though, with the correct oil and level it should have been a pretty moot point. I really have to think there were other factors at play here that contributed to the cause of failure.
You don't actually state where the failure occured. Was it the LNE IMS bearing, a spun bearing, piston to wall collision? All are documented failure modes (amoung others, of course) due to oil starvation, that will yield metal in the filter, and are well documented. Personally, I think no street car is a track car regardless og manufacturer, without extensive engine mods, unless you are "tracking" at street speed/levels, or slightly higher. Where did that first quart "go", assuming you were slightly overfilled, as you should have been for track use? Whatever caused the loss of the first quart (!) probably also caused the loss of another quart or more, and there is the real culprit. Of course, you have to admit, that any car that has been tracked is ALWAYS going to be more suspect for a failure than one that hasn't, as you can't know what the REAL history of the engine is. The hard braking and hard acceleration, all add to loosening debris, that can block oil passages, as well as foaming in locations that with a borderline pressure might be catastrophic. Too many questions, and not enough data to make a meaningful assesment, really.
The X51 modification, with 2 extra pick up points, is to me, the basics required to prevent this starvation, or more inexpensively, an Accusump, that maintains the oil pressure from an external pressurized reservoir. I don't track, but as an engineer, it's not hard to see where improvements for track use would be helpful, both in lubrication and cooling. No pick up extension on a deep sump is worse than no deep sump at all, due to the pick up being closer to the foaming level during a turn, though, with the correct oil and level it should have been a pretty moot point. I really have to think there were other factors at play here that contributed to the cause of failure.
You don't actually state where the failure occured. Was it the LNE IMS bearing, a spun bearing, piston to wall collision? All are documented failure modes (amoung others, of course) due to oil starvation, that will yield metal in the filter, and are well documented. Personally, I think no street car is a track car regardless og manufacturer, without extensive engine mods, unless you are "tracking" at street speed/levels, or slightly higher. Where did that first quart "go", assuming you were slightly overfilled, as you should have been for track use? Whatever caused the loss of the first quart (!) probably also caused the loss of another quart or more, and there is the real culprit. Of course, you have to admit, that any car that has been tracked is ALWAYS going to be more suspect for a failure than one that hasn't, as you can't know what the REAL history of the engine is. The hard braking and hard acceleration, all add to loosening debris, that can block oil passages, as well as foaming in locations that with a borderline pressure might be catastrophic. Too many questions, and not enough data to make a meaningful assesment, really.
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Insaty (07-21-2023)
11-13-2012, 07:53 PM
#19
Rennlist Member
Thread Starter
Oil starvation of high G turns (one direction only, I think, though I can't recall which) has been documented for a long time. I re-read this several times, and I am sorry for your financial loss. Many of us fear that same loss. You car may have failed on the street, the exact same way, regardless...you will never know.
The X51 modification, with 2 extra pick up points, is to me, the basics required to prevent this starvation, or more inexpensively, an Accusump, that maintains the oil pressure from an external pressurized reservoir. I don't track, but as an engineer, it's not hard to see where improvements for track use would be helpful, both in lubrication and cooling. No pick up extension on a deep sump is worse than no deep sump at all, due to the pick up being closer to the foaming level during a turn, though, with the correct oil and level it should have been a pretty moot point. I really have to think there were other factors at play here that contributed to the cause of failure.
You don't actually state where the failure occured. Was it the LNE IMS bearing, a spun bearing, piston to wall collision? All are documented failure modes (amoung others, of course) due to oil starvation, that will yield metal in the filter, and are well documented. Personally, I think no street car is a track car regardless og manufacturer, without extensive engine mods, unless you are "tracking" at street speed/levels, or slightly higher. Where did that first quart "go", assuming you were slightly overfilled, as you should have been for track use? Whatever caused the loss of the first quart (!) probably also caused the loss of another quart or more, and there is the real culprit. Of course, you have to admit, that any car that has been tracked is ALWAYS going to be more suspect for a failure than one that hasn't, as you can't know what the REAL history of the engine is. The hard braking and hard acceleration, all add to loosening debris, that can block oil passages, as well as foaming in locations that with a borderline pressure might be catastrophic. Too many questions, and not enough data to make a meaningful assesment, really.
The X51 modification, with 2 extra pick up points, is to me, the basics required to prevent this starvation, or more inexpensively, an Accusump, that maintains the oil pressure from an external pressurized reservoir. I don't track, but as an engineer, it's not hard to see where improvements for track use would be helpful, both in lubrication and cooling. No pick up extension on a deep sump is worse than no deep sump at all, due to the pick up being closer to the foaming level during a turn, though, with the correct oil and level it should have been a pretty moot point. I really have to think there were other factors at play here that contributed to the cause of failure.
You don't actually state where the failure occured. Was it the LNE IMS bearing, a spun bearing, piston to wall collision? All are documented failure modes (amoung others, of course) due to oil starvation, that will yield metal in the filter, and are well documented. Personally, I think no street car is a track car regardless og manufacturer, without extensive engine mods, unless you are "tracking" at street speed/levels, or slightly higher. Where did that first quart "go", assuming you were slightly overfilled, as you should have been for track use? Whatever caused the loss of the first quart (!) probably also caused the loss of another quart or more, and there is the real culprit. Of course, you have to admit, that any car that has been tracked is ALWAYS going to be more suspect for a failure than one that hasn't, as you can't know what the REAL history of the engine is. The hard braking and hard acceleration, all add to loosening debris, that can block oil passages, as well as foaming in locations that with a borderline pressure might be catastrophic. Too many questions, and not enough data to make a meaningful assesment, really.
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Insaty (07-21-2023)
11-13-2012, 07:55 PM
#20
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Thread Starter
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Insaty (07-21-2023)
11-13-2012, 08:03 PM
#21
Really sorry to hear about your bad experience. That said, I dont think you can blame engine design if you are racing your 11 year old, modded 996 around a race track and the engine goes.
I would think if you bought the car modded for track use it would be probable that it was ran hard (raced). Do you really know about the quaility of work on a modded car if you didnt DIY?
I guess I cant relate because I dont see taking my weekend / good weather fun to drive 996 to a race track. Now, if I had a race prepped Porsche that was track only, I would realize that it could have a major failure at any time on race day. You tow it home, repair, then go race some more. You certainly dont blame Porsche. I cant find anything in my owners manual about tracking my 996.
It would be like taking my wifes new GT to the drag stip. Race all day until the clutch gave out, then lament how much Fords suck and they cant build a clutch. Once again, sorry but I dont know what you expected.
I would think if you bought the car modded for track use it would be probable that it was ran hard (raced). Do you really know about the quaility of work on a modded car if you didnt DIY?
I guess I cant relate because I dont see taking my weekend / good weather fun to drive 996 to a race track. Now, if I had a race prepped Porsche that was track only, I would realize that it could have a major failure at any time on race day. You tow it home, repair, then go race some more. You certainly dont blame Porsche. I cant find anything in my owners manual about tracking my 996.
It would be like taking my wifes new GT to the drag stip. Race all day until the clutch gave out, then lament how much Fords suck and they cant build a clutch. Once again, sorry but I dont know what you expected.
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Insaty (07-21-2023)
11-13-2012, 08:18 PM
#22
Rennlist Member
Thread Starter
Really sorry to hear about your bad experience. That said, I dont think you can blame engine design if you are racing your 11 year old, modded 996 around a race track and the engine goes.
I would think if you bought the car modded for track use it would be probable that it was ran hard (raced). Do you really know about the quaility of work on a modded car if you didnt DIY?
I guess I cant relate because I dont see taking my weekend / good weather fun to drive 996 to a race track. Now, if I had a race prepped Porsche that was track only, I would realize that it could have a major failure at any time on race day. You tow it home, repair, then go race some more. You certainly dont blame Porsche. I cant find anything in my owners manual about tracking my 996.
It would be like taking my wifes new GT to the drag stip. Race all day until the clutch gave out, then lament how much Fords suck and they cant build a clutch. Once again, sorry but I dont know what you expected.
I would think if you bought the car modded for track use it would be probable that it was ran hard (raced). Do you really know about the quaility of work on a modded car if you didnt DIY?
I guess I cant relate because I dont see taking my weekend / good weather fun to drive 996 to a race track. Now, if I had a race prepped Porsche that was track only, I would realize that it could have a major failure at any time on race day. You tow it home, repair, then go race some more. You certainly dont blame Porsche. I cant find anything in my owners manual about tracking my 996.
It would be like taking my wifes new GT to the drag stip. Race all day until the clutch gave out, then lament how much Fords suck and they cant build a clutch. Once again, sorry but I dont know what you expected.
). As i stated previously I watched a lot of other cars handle the event without incident. I was the only person with a Porsche and the only person with a failure. It was my first event and I am not skilled enough to push the car anywhere near it's limits. If you have been to any DE track events, you would know that all levels of cars attend (this event had everything from VW GTI's and BMW M3's to Dodge Challengers).The car didn't meet my expectations, I learned a few things, and I took the time to pass on my information to others. My conversations with those who specialize in the M96 engine was eye opening in a bad way. If you don't track your car then I guess you can dismiss everything I said. If you do I suggest you look into my findings. I don't think you should run out and sell your 996 but i do think that precautions need to be taken to run the car on the track - even at a DE event. I also wouldn't chose to buy another M96 for my desired use of the car (street with a few DE events). As far as expectations go... I would not have taken the time to post my findings if there were a moderate repair needed after a track event - and I would not be overly disappointed or surprised to see something break at the track. What happened to me was a complete engine failure which is outside of my expectations for a DE event. I contributed my findings to help others avoid the same fate.
I'm not surprised that my opinion about the M96 is met with skepticism by a group of individuals who have made the decision to own one. Keep in mind that I am one of those individuals.
FWIW- I have not completely dismissed the brand as I am purchasing a Cayman.
Last edited by slicer; 11-13-2012 at 09:29 PM.
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Insaty (07-21-2023)
11-13-2012, 08:44 PM
#23
This plus effectively the baffle is pulled away from the pick up tube by the amount equal to the thickness of the deep sump. The thicker the worse because the baffle prevents the oil from sloshing around when the car turns. The pick up "region" will be less protected by the baffle if moved away frome it.
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Insaty (07-21-2023)
11-13-2012, 08:54 PM
#24
Rennlist Member
Thread Starter
This plus effectively the baffle is pulled away from the pick up tube by the amount equal to the thickness of the deep sump. The thicker the worse because the baffle prevents the oil from sloshing around when the car turns. The pick up "region" will be less protected by the baffle if moved away frome it.
I think the baffle remains at a fixed point in relation to the pick up tube (especially if no pick up tube spacer is installed). The pick up tube comes from the top. And there is a spacer (presumably the same thickness as the oil pan spacer) installed below the baffle (not above).
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Insaty (07-21-2023)
11-13-2012, 09:01 PM
#25
See the install instructions in this link. http://www.lnengineering.com/deepsump.html
I think the baffle remains at a fixed point in relation to the pick up tube (especially if no pick up tube spacer is installed). The pick up tube comes from the top. And there is a spacer (presumably the same thickness as the oil pan spacer) installed below the baffle (not above).
I think the baffle remains at a fixed point in relation to the pick up tube (especially if no pick up tube spacer is installed). The pick up tube comes from the top. And there is a spacer (presumably the same thickness as the oil pan spacer) installed below the baffle (not above).
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Insaty (07-21-2023)
11-13-2012, 09:51 PM
#26
Former Vendor
Your original post is a concise summary for sure. You are very lucky that you secured a buyer at that price as quickly as you did.
With these engines its all luck. Some are ran in stock form on the street and track for years and never break, other owners have had failures like this one and some have had more than one engine fail. The record (here) for one individual is 4 failed engines. We finally got him on the track without issues for 3 years now, which I suppose is a miracle.
Since you did not love the car and didn't want to keep it forever, you made the right choice. Like I told you on the phone, our engine solution only makes sense if the owner wants the car forever and doesn't want to end up having this scenario play out again. More people love their 996s enough to spend more on the engine than the car is worth than you'd ever imagine, which is why we have been slammed with 6-8 month back logs continually since before 2006.
That said over and over again we find that the external bolt on "fixes" for the oil supposed oil system issues these engines have do not solve the problems. There is also a very good chance that the engine was tired, had been previously injured and its demise simply occurred in your hands. Looks like the last guy got all the fun and left you the sloppy seconds.
Glad to see that we are still at the top of the food chain price wise, its time to go up on the prices though, since OEM Porsche engines are now more than ours and I simply can't have that! :-)
(Hell we were building 15-18K engines years ago when a new crate engine from Porsche was 5-7K!)
With these engines its all luck. Some are ran in stock form on the street and track for years and never break, other owners have had failures like this one and some have had more than one engine fail. The record (here) for one individual is 4 failed engines. We finally got him on the track without issues for 3 years now, which I suppose is a miracle.
Since you did not love the car and didn't want to keep it forever, you made the right choice. Like I told you on the phone, our engine solution only makes sense if the owner wants the car forever and doesn't want to end up having this scenario play out again. More people love their 996s enough to spend more on the engine than the car is worth than you'd ever imagine, which is why we have been slammed with 6-8 month back logs continually since before 2006.
That said over and over again we find that the external bolt on "fixes" for the oil supposed oil system issues these engines have do not solve the problems. There is also a very good chance that the engine was tired, had been previously injured and its demise simply occurred in your hands. Looks like the last guy got all the fun and left you the sloppy seconds.
Glad to see that we are still at the top of the food chain price wise, its time to go up on the prices though, since OEM Porsche engines are now more than ours and I simply can't have that! :-)
(Hell we were building 15-18K engines years ago when a new crate engine from Porsche was 5-7K!)
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Insaty (07-21-2023)
11-13-2012, 10:03 PM
#27
Rennlist Member
Thread Starter
Your original post is a concise summary for sure. You are very lucky that you secured a buyer at that price as quickly as you did.
With these engines its all luck. Some are ran in stock form on the street and track for years and never break, other owners have had failures like this one and some have had more than one engine fail. The record (here) for one individual is 4 failed engines. We finally got him on the track without issues for 3 years now, which I suppose is a miracle.
Since you did not love the car and didn't want to keep it forever, you made the right choice. Like I told you on the phone, our engine solution only makes sense if the owner wants the car forever and doesn't want to end up having this scenario play out again. More people love their 996s enough to spend more on the engine than the car is worth than you'd ever imagine, which is why we have been slammed with 6-8 month back logs continually since before 2006.
That said over and over again we find that the external bolt on "fixes" for the oil supposed oil system issues these engines have do not solve the problems. There is also a very good chance that the engine was tired, had been previously injured and its demise simply occurred in your hands. Looks like the last guy got all the fun and left you the sloppy seconds.
Glad to see that we are still at the top of the food chain price wise, its time to go up on the prices though, since OEM Porsche engines are now more than ours and I simply can't have that! :-)
(Hell we were building 15-18K engines years ago when a new crate engine from Porsche was 5-7K!)
With these engines its all luck. Some are ran in stock form on the street and track for years and never break, other owners have had failures like this one and some have had more than one engine fail. The record (here) for one individual is 4 failed engines. We finally got him on the track without issues for 3 years now, which I suppose is a miracle.
Since you did not love the car and didn't want to keep it forever, you made the right choice. Like I told you on the phone, our engine solution only makes sense if the owner wants the car forever and doesn't want to end up having this scenario play out again. More people love their 996s enough to spend more on the engine than the car is worth than you'd ever imagine, which is why we have been slammed with 6-8 month back logs continually since before 2006.
That said over and over again we find that the external bolt on "fixes" for the oil supposed oil system issues these engines have do not solve the problems. There is also a very good chance that the engine was tired, had been previously injured and its demise simply occurred in your hands. Looks like the last guy got all the fun and left you the sloppy seconds.
Glad to see that we are still at the top of the food chain price wise, its time to go up on the prices though, since OEM Porsche engines are now more than ours and I simply can't have that! :-)
(Hell we were building 15-18K engines years ago when a new crate engine from Porsche was 5-7K!)
Last edited by slicer; 11-13-2012 at 10:22 PM.
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Insaty (07-21-2023)
11-14-2012, 12:26 AM
#28
Slicer, I know what the previous owner did to you sucks but there are warnings all through the LNE info about the pan mod. LNE info warns:
"Stickier tires will make the problem worse, as do other modifications to the car, which allow for greater G’s."
and:
"Experienced drivers with R-compound or race tires should consider a more proactive approach to preventing oil starvation with the installation of an Accusump system, 2 Quart Deep Sump, or Dual Tandem Oil pumps as outlined on our Oil Starvation Prevention page."
Sounds like your cars suspension was modded to withstand more G skidpad force but maybe the engine was not equally modded? In other words the P.O. may have caused major damage before you got it (Just like JR said)?
I do have a question though. Did you happen to do a recent oil change / filter inspection on this car? If so, was there anything in the filter?
"Stickier tires will make the problem worse, as do other modifications to the car, which allow for greater G’s."
and:
"Experienced drivers with R-compound or race tires should consider a more proactive approach to preventing oil starvation with the installation of an Accusump system, 2 Quart Deep Sump, or Dual Tandem Oil pumps as outlined on our Oil Starvation Prevention page."
Sounds like your cars suspension was modded to withstand more G skidpad force but maybe the engine was not equally modded? In other words the P.O. may have caused major damage before you got it (Just like JR said)?
I do have a question though. Did you happen to do a recent oil change / filter inspection on this car? If so, was there anything in the filter?
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Insaty (07-21-2023)
11-14-2012, 12:48 AM
#29
Rennlist Member
Thread Starter
Slicer, I know what the previous owner did to you sucks but there are warnings all through the LNE info about the pan mod. LNE info warns:
"Stickier tires will make the problem worse, as do other modifications to the car, which allow for greater G’s."
and:
"Experienced drivers with R-compound or race tires should consider a more proactive approach to preventing oil starvation with the installation of an Accusump system, 2 Quart Deep Sump, or Dual Tandem Oil pumps as outlined on our Oil Starvation Prevention page."
Sounds like your cars suspension was modded to withstand more G skidpad force but maybe the engine was not equally modded? In other words the P.O. may have caused major damage before you got it (Just like JR said)?
I do have a question though. Did you happen to do a recent oil change / filter inspection on this car? If so, was there anything in the filter?
"Stickier tires will make the problem worse, as do other modifications to the car, which allow for greater G’s."
and:
"Experienced drivers with R-compound or race tires should consider a more proactive approach to preventing oil starvation with the installation of an Accusump system, 2 Quart Deep Sump, or Dual Tandem Oil pumps as outlined on our Oil Starvation Prevention page."
Sounds like your cars suspension was modded to withstand more G skidpad force but maybe the engine was not equally modded? In other words the P.O. may have caused major damage before you got it (Just like JR said)?
I do have a question though. Did you happen to do a recent oil change / filter inspection on this car? If so, was there anything in the filter?
I had the oil changed 5k miles ago in March along with a new clutch, LN Engineering IMS bearing upgrade, and cam cover seals. No metal observed in the filter.
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Insaty (07-21-2023)
11-14-2012, 01:08 AM
#30
Rennlist Member
Slicer, thank you for your very well written public service announcement. Sorry you learned these things the hard way & I am glad you chose to go the 9A1 Cayman route. I think you will be in love again soon! 
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Insaty (07-21-2023)