Oil starvation....
#31
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Originally Posted by insite
from what i understand, it's not an issue on the 3.6L, but IS an issue on the 3.4L and on the 987 boxsters. any truth to this?
on my track car (boxster), sustained high G cornering (>1.0G) will cause some valve chatter that goes away after a few seconds. it's almost like the lifters sag from either starvation or from oil saturated with air. i always attributed this to the pickup point in the car's sump & the sump design; i've seen other boxsters and 996's do this. no logged data to verify pressure drops, just a noticable symptom.
on my track car (boxster), sustained high G cornering (>1.0G) will cause some valve chatter that goes away after a few seconds. it's almost like the lifters sag from either starvation or from oil saturated with air. i always attributed this to the pickup point in the car's sump & the sump design; i've seen other boxsters and 996's do this. no logged data to verify pressure drops, just a noticable symptom.
#32
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Originally Posted by insite
from what i understand, it's not an issue on the 3.6L, but IS an issue on the 3.4L and on the 987 boxsters. any truth to this?
on my track car (boxster), sustained high G cornering (>1.0G) will cause some valve chatter that goes away after a few seconds. it's almost like the lifters sag from either starvation or from oil saturated with air. i always attributed this to the pickup point in the car's sump & the sump design; i've seen other boxsters and 996's do this. no logged data to verify pressure drops, just a noticable symptom.
on my track car (boxster), sustained high G cornering (>1.0G) will cause some valve chatter that goes away after a few seconds. it's almost like the lifters sag from either starvation or from oil saturated with air. i always attributed this to the pickup point in the car's sump & the sump design; i've seen other boxsters and 996's do this. no logged data to verify pressure drops, just a noticable symptom.
As has been noted, Jim had significant expereince tracking the M96 motor. I traacked my 996CAB for several years really pushing it hard and never experienced and oil starvation issues. However, I moved to a GT3 to give me the "proper" platform to full exploit as my skill level continues to increase. The only thing I would move to from here is a Cup car but I can't make that kind of committment just as I love driving the 3 around town from time to time.
#33
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Originally Posted by JimB
Dell beat me to it but my question would be, what evidence is there that oil starvation is a problem? I don't think you can take a few examples where the oil pressure gauge dips in corners and use it to come to that conclusion. Not when we've seen hundreds of thousands of 996 track miles without oiling kits with relatively few engine problems.
Jim
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#34
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Originally Posted by JimB
Dell beat me to it but my question would be, what evidence is there that oil starvation is a problem? I don't think you can take a few examples where the oil pressure gauge dips in corners and use it to come to that conclusion. Not when we've seen hundreds of thousands of 996 track miles without oiling kits with relatively few engine problems.
Jim
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Originally Posted by murphyslaw1978
I am all for a different conclusion as to why the gauge drops in corners. The trouble is, I can't think of one. If anyone knows, then please post it here!
#36
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The fact is, ANY drop in oil pressure while maintaining rpm's is a result of less oil pumping through the engine which translates into less than optimum oiling of the engine. I sure would't want to be running my engine at 7000 rpm and see the pressure drop. I guess my first response would be to remove the Mobil water from the engine and put in a better oil and then go on from there.
Most likely cause if the pressure returns after the sweep, would be air being sucked up by the pickup. Not a good thing.
Most likely cause if the pressure returns after the sweep, would be air being sucked up by the pickup. Not a good thing.
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Originally Posted by wdonovan
Don't think you're gonna get an answer here (other than mine). Thinking seems to be that without flight recorder data, we should all refuse to even discuss the possible causes of oil starvation. Ah, youthful exuberance!
#38
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Originally Posted by insite
from what i understand, it's not an issue on the 3.6L, but IS an issue on the 3.4L and on the 987 boxsters. any truth to this?
on my track car (boxster), sustained high G cornering (>1.0G) will cause some valve chatter that goes away after a few seconds. it's almost like the lifters sag from either starvation or from oil saturated with air. i always attributed this to the pickup point in the car's sump & the sump design; i've seen other boxsters and 996's do this. no logged data to verify pressure drops, just a noticable symptom.
on my track car (boxster), sustained high G cornering (>1.0G) will cause some valve chatter that goes away after a few seconds. it's almost like the lifters sag from either starvation or from oil saturated with air. i always attributed this to the pickup point in the car's sump & the sump design; i've seen other boxsters and 996's do this. no logged data to verify pressure drops, just a noticable symptom.
Where is the smoking gun or better still all the "smoldering motors" from oil starvation?
I've been tracking my Boxster (on R Compounds) now for 6 years and I have not experienced the type of valve clatter you are describing. Even on long sweepers like the Carousel at Road America or the long South 1 and 2 combo at Autobahn. Additionally, I have not noticed anyone else having these problems at the events I have been at.
I'm not saying you aren't experiencing it. I'm only saying that in 6 years I never have.
#39
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Originally Posted by Ray S
The problem (with this alleged problem) is where are the all the broken cars?? Where are all the trashed motors??? After all literally hundreds (probably thousands) of M96 Boxsters and Carerra's are being taken to tracks all over the world. There are tons of these cars at every event that I attend. There have been a few "my cousins, sisters, friend knows a guy who had his engine blow" type reports. But certainly no RMS or "Bob" type groundswells.
Where is the smoking gun or better still all the "smoldering motors" from oil starvation?
I've been tracking my Boxster (on R Compounds) now for 6 years and I have not experienced the type of valve clatter you are describing. Even on long sweepers like the Carousel at Road America or the long South 1 and 2 combo at Autobahn. Additionally, I have not noticed anyone else having these problems at the events I have been at.
I'm not saying you aren't experiencing it. I'm only saying that in 6 years I never have.
Where is the smoking gun or better still all the "smoldering motors" from oil starvation?
I've been tracking my Boxster (on R Compounds) now for 6 years and I have not experienced the type of valve clatter you are describing. Even on long sweepers like the Carousel at Road America or the long South 1 and 2 combo at Autobahn. Additionally, I have not noticed anyone else having these problems at the events I have been at.
I'm not saying you aren't experiencing it. I'm only saying that in 6 years I never have.
I would be interested to find out how many people actually notice the gauge dropping and have subsequently run 30,000 track miles without performing the engine update.
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Originally Posted by JimB
Left or right hand corners? Sweepers or tight turns? Approx. speed? I'm really curious. I have thousands of track miles in 3.4Ls and this is the first I've heard of valve chatter.
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Originally Posted by Ray S
Where is the smoking gun or better still all the "smoldering motors" from oil starvation?
Originally Posted by Ray S
I've been tracking my Boxster (on R Compounds) now for 6 years and I have not experienced the type of valve clatter you are describing. Even on long sweepers like the Carousel at Road America or the long South 1 and 2 combo at Autobahn. Additionally, I have not noticed anyone else having these problems at the events I have been at.