How many 15-16 gt3's have engine replaced?
#2041
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Does anyone know the last month of production for the 991.1 GT3?
Just keeping notes on factory "G" motor and replacement motors to see if there are more upgrades and/ or different outcomes ......
Thx
Just keeping notes on factory "G" motor and replacement motors to see if there are more upgrades and/ or different outcomes ......
Thx
#2042
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#2046
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Loose particles of DLC make an efficient grinding media.
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#2049
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Macca, 80 hours of track time is impressive.
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#2050
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#2051
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I think Macca meant that 6k track miles should be around 80 hours, using an average speed of 75 mph, which sounds about right for the tracks I run. My car has/had
close to 17k total miles, the balance of which mostly included driving to tracks and running with the Smokies group.
One question I have is why there is nothing in the Porsche 991 GT3 track maintenance guidelines for engine rebuilds or even inspections. Even at 12k track miles, the recommended maintenance only relates to suspension and fluid changes. That doesn't seem realistic, even if there wasn't a history of problems. If you are driving the car hard, there is no way any race shop would let an engine go 160 hours of run time on a track without a rebuild. Believe it or not, when I asked my race shop about my rear axle failure, they didn't find it astonishing at all. They replace axles on their Cup cars as a preventative measure after extended track time, the rationale being that the metal does become brittle after significant abuse. I'm just a messenger here, so please don't tell me how stupid I am for believing that. I'm just relaying the info for the good of the community. BTW, they've worked with many of the top racing teams in the country and do the maintenance for the Porsche driving school, so they aren't amateurs.
My fear is that Porsche assumes some modal usage for the car, rather than factoring in outliers like myself, which is strange, given the culture of litigation that we live in. It is causing me to wonder whether the "safest" route is to move to a GT4 Clubsport and take a more conservative maintenance approach. I'm not sure yet whether I want the hassle and cost associated with that, but I may have to reset a lot of my expectations, given the value I place on my life. This is just a sport after all, addictive as it may be.
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One question I have is why there is nothing in the Porsche 991 GT3 track maintenance guidelines for engine rebuilds or even inspections. Even at 12k track miles, the recommended maintenance only relates to suspension and fluid changes. That doesn't seem realistic, even if there wasn't a history of problems. If you are driving the car hard, there is no way any race shop would let an engine go 160 hours of run time on a track without a rebuild. Believe it or not, when I asked my race shop about my rear axle failure, they didn't find it astonishing at all. They replace axles on their Cup cars as a preventative measure after extended track time, the rationale being that the metal does become brittle after significant abuse. I'm just a messenger here, so please don't tell me how stupid I am for believing that. I'm just relaying the info for the good of the community. BTW, they've worked with many of the top racing teams in the country and do the maintenance for the Porsche driving school, so they aren't amateurs.
My fear is that Porsche assumes some modal usage for the car, rather than factoring in outliers like myself, which is strange, given the culture of litigation that we live in. It is causing me to wonder whether the "safest" route is to move to a GT4 Clubsport and take a more conservative maintenance approach. I'm not sure yet whether I want the hassle and cost associated with that, but I may have to reset a lot of my expectations, given the value I place on my life. This is just a sport after all, addictive as it may be.
#2052
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I suspect that, for a 50K mile / 4 year warranty period, Porsche estimates that there will be an average of X track miles during that period, which will result in various probabilities for various types of failures during that period, with the more likely failure modes prevented by the regular and track maintenance schedules. I doubt they anticipated a significant number of engine failures, or failures of other costly or safety-critical components not addressed by the scheduled maintenance. Prohibiting slicks would be factored into all of this, so that's a substantial difference in comparing this car with race cars.
If a car is driven the full 50K miles in 4 years, and say that includes 20K track miles (5K track miles a year would be roughly 35 track days a year, which is very plausible), that would be roughly 250 track hours, and I think it would be reasonable to expect a need for an engine rebuild not too long after that, but not well before that. I've heard of 996 cup car engines going 200+ hours before rebuild.
If a car is driven the full 50K miles in 4 years, and say that includes 20K track miles (5K track miles a year would be roughly 35 track days a year, which is very plausible), that would be roughly 250 track hours, and I think it would be reasonable to expect a need for an engine rebuild not too long after that, but not well before that. I've heard of 996 cup car engines going 200+ hours before rebuild.
#2053
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The new Cup has recommended rebuild intervals of 100hrs and supposedly uses the same basic engine architecture as 991 GT3/RS, although we really won't know true overlap until we can compare parts. For reference, the prior Mezger-based Cups had 50hr recommended rebuilds.
Porsche clearly has a lot of faith in the new motor. I just hope it's fully debugged for Gen II cars (and the Cup).
Porsche clearly has a lot of faith in the new motor. I just hope it's fully debugged for Gen II cars (and the Cup).
#2054
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I suspect that, for a 50K mile / 4 year warranty period, Porsche estimates that there will be an average of X track miles during that period, which will result in various probabilities for various types of failures during that period, with the more likely failure modes prevented by the regular and track maintenance schedules. I doubt they anticipated a significant number of engine failures, or failures of other costly or safety-critical components not addressed by the scheduled maintenance. Prohibiting slicks would be factored into all of this, so that's a substantial difference in comparing this car with race cars.
If a car is driven the full 50K miles in 4 years, and say that includes 20K track miles (5K track miles a year would be roughly 35 track days a year, which is very plausible), that would be roughly 250 track hours, and I think it would be reasonable to expect a need for an engine rebuild not too long after that, but not well before that. I've heard of 996 cup car engines going 200+ hours before rebuild.
If a car is driven the full 50K miles in 4 years, and say that includes 20K track miles (5K track miles a year would be roughly 35 track days a year, which is very plausible), that would be roughly 250 track hours, and I think it would be reasonable to expect a need for an engine rebuild not too long after that, but not well before that. I've heard of 996 cup car engines going 200+ hours before rebuild.