Are Porsche boxer engines inherently fragile?
01-15-2013, 06:00 PM
#16
Nordschleife Master
my first 911 was sold with 178,000 miles on the odometer...
my colleague's 993 currently has over 250K miles
but they're clearly not Hondas
my colleague's 993 currently has over 250K miles
but they're clearly not Hondas
The reason I'm asking is that after reading many threads on many different forums and looking for used Porsches, it seems like people feel that 50,000 or even 30,000 miles on a Porsche is a lot of miles.
Speaking to some dealers on cars with over 30K their reaction is, well you have to understand that car is priced lower "because it has a lot of miles", what's up with that.
30,000 is not a lot of miles, not in my book.
I purchased a 1988 Honda civic hatchback base model, 5 speed, not even a CX or DX this was bare bones, didn't even come with a stereo for around $9,600.
I then proceeded to put on over 330,000 miles on it over the almost 20 years I owned it, and the engine never died, it was the rest of the car that died.
In many threads regarding Porsche vehicles when someone hits 100,000 miles it seems like some kind of miracle has happened, like people are surprised.
Am I wrong in assuming that if I spend over $100K on a Porsche that the car should be able to rack up 200,000 trouble free miles?
I currently have a 2005 Porsche Boxster with over 50,000K and after my experience with my Honda, I was assuming I could easily get another 100,000 trouble free miles from the drivetrain.
A Porsche engine should be more robust than a Honda 4 banger, shouldn't it.
I guess what I'm trying to figure out is what is the lifespan of a properly maintained Porsche engine?
Speaking to some dealers on cars with over 30K their reaction is, well you have to understand that car is priced lower "because it has a lot of miles", what's up with that.
30,000 is not a lot of miles, not in my book.
I purchased a 1988 Honda civic hatchback base model, 5 speed, not even a CX or DX this was bare bones, didn't even come with a stereo for around $9,600.
I then proceeded to put on over 330,000 miles on it over the almost 20 years I owned it, and the engine never died, it was the rest of the car that died.
In many threads regarding Porsche vehicles when someone hits 100,000 miles it seems like some kind of miracle has happened, like people are surprised.
Am I wrong in assuming that if I spend over $100K on a Porsche that the car should be able to rack up 200,000 trouble free miles?
I currently have a 2005 Porsche Boxster with over 50,000K and after my experience with my Honda, I was assuming I could easily get another 100,000 trouble free miles from the drivetrain.
A Porsche engine should be more robust than a Honda 4 banger, shouldn't it.
I guess what I'm trying to figure out is what is the lifespan of a properly maintained Porsche engine?
01-15-2013, 07:47 PM
#17
Porsche engines are generally reliable but each series seem to have its own weak point(s) (IMS et al.). The owner of my independent Porsche shop had 218K miles on his Boxster. He finally sold the car but kept the engine, took it apart since he owned the car from day 1. This company does a lot of engine rebuilds for all Porsche cars. He said the the tolerances were within 0.2% of a new engine specs after 218K miles. This car was maintained by the book with no excessive maintenance.
01-15-2013, 09:48 PM
#18
Racer
I am pleased to see these responses. When reading many posts on this forum one begins to think of 30,000 miles as a lot, since many (including myself) seem to drive these cars a very few miles per year. I am slowly discarding my other vehicles, so my 997.2 will soon begin to see much more action. I expect it to hold together. I hope it does.
01-15-2013, 09:52 PM
#19
This truism that most wear occurs at engine start has been around a long time, and I believe based on empirical evidence false or at least is not the biggest baddest factor in engine wear.
I mean look around you. Every car, not only Porsches, have engines all of which get started all the time at all temps and there doesn't seem to be a significant number of worn out engines.
(How many times do you think my 02 Boxster's engine has been started over the last 11 years and 263K miles?)
Barring a car that sees so little use that the engine sits for a long period of time (no real idea of what in this context would be a long period of time) between engine starts I say this wear on cold start just isn't a real factor in modern engine longevity.
What I believe is more likely the factor is engine engine wear which is chemical in nature.
It is the constant exposure by the ever increasing levels of acidity in the engine oil to the engine components that is the real wear culprit.
This acidity attacks every metal surface and seal and gasket that is contact with the engine oil.
Now some corrosion on the inner walls of an engine block is not going to be an engine killer.
But having oil lay stagnant in the bearing voids, in the/around the rings, piston/cylinders, lay stagnant in the zero lash lifters, in the chain tensioners, and other places will over time see these areas affected by the corrosive action of the oil, that is the water in the oil that is acidic.
Remember that as soon as the engine stops running oil begins to stratify. Water and oil do not remain mixed so a thin layer of corrosive water begins to form.
In my opinion then it is clear that keeping this acid build up down is paramount.
Sure modern oils come with additives to neutralize the acids that naturally form in engine oil, but there is a limit. What works for one owner and his usage of his vehicle may not work for another owner and his different usage of his vehicle.
One way is to avoid using the car in such a way that leads to a build up of water/unburned gasoline in the engine oil. This is not as easy as it might appear for reasons I won't cover here.
Another course of action is to assume this acid builds up regardless of how the car is driven and periodically remove the oil with its load of acid. This is fewer words is change the oil/filter.
As I have mentioned uncounted times reasonable oil/filter service intervals is about the best thing an owner can do to prolong the life of the engine.
Second best thing, and it really is tied with reasonable oil/filter service intervals, and that is give/treat the engine with a reasonable amount of mechanical empathy.
I mean look around you. Every car, not only Porsches, have engines all of which get started all the time at all temps and there doesn't seem to be a significant number of worn out engines.
(How many times do you think my 02 Boxster's engine has been started over the last 11 years and 263K miles?)
Barring a car that sees so little use that the engine sits for a long period of time (no real idea of what in this context would be a long period of time) between engine starts I say this wear on cold start just isn't a real factor in modern engine longevity.
What I believe is more likely the factor is engine engine wear which is chemical in nature.
It is the constant exposure by the ever increasing levels of acidity in the engine oil to the engine components that is the real wear culprit.
This acidity attacks every metal surface and seal and gasket that is contact with the engine oil.
Now some corrosion on the inner walls of an engine block is not going to be an engine killer.
But having oil lay stagnant in the bearing voids, in the/around the rings, piston/cylinders, lay stagnant in the zero lash lifters, in the chain tensioners, and other places will over time see these areas affected by the corrosive action of the oil, that is the water in the oil that is acidic.
Remember that as soon as the engine stops running oil begins to stratify. Water and oil do not remain mixed so a thin layer of corrosive water begins to form.
In my opinion then it is clear that keeping this acid build up down is paramount.
Sure modern oils come with additives to neutralize the acids that naturally form in engine oil, but there is a limit. What works for one owner and his usage of his vehicle may not work for another owner and his different usage of his vehicle.
One way is to avoid using the car in such a way that leads to a build up of water/unburned gasoline in the engine oil. This is not as easy as it might appear for reasons I won't cover here.
Another course of action is to assume this acid builds up regardless of how the car is driven and periodically remove the oil with its load of acid. This is fewer words is change the oil/filter.
As I have mentioned uncounted times reasonable oil/filter service intervals is about the best thing an owner can do to prolong the life of the engine.
Second best thing, and it really is tied with reasonable oil/filter service intervals, and that is give/treat the engine with a reasonable amount of mechanical empathy.
My Boxster's owners manual says to change the engine oil every 20,000 miles or 2 years which ever comes first. That's 4 times the interval of the past.
I cut that down by half and do my oil changes every 10,000 miles, maybe I should do them sooner, who knows.
When you send your oil in for analysis do they check for acidity?
Maybe having an oil change interval of this length might contribute to engine failures/issues.
I was going to change the coolant in my car but the manual says the coolant is a lifetime product and never needs to be changes.
Porsche must have some special chemistry because the longest interval I've read is 5 years.
