Hit the Rev Limiter

[Brucelee]

"The lack of revs(storing a car long enough for moisture to work it's magic)"

From the standpoint of engine longevity, this is probably not the correct way to frame it. I am certainly not suggesting you park your Porsche to preserve it.

I think the data shows that driving your Porsche to the red line on a daily basis will certainly shorten the drive train's life vs. a more prudent way of driving.

This is supported both in theory and in practice.

To wit, the useful life of just about any race car is very very short, even though these cars are built to specifically run at top RPMS (blue printed engines, forged metals, oil changes at every race etc.).

If running these cars at top RPM was "good for them" they would have a nice long lifespan.

They do not.

Nor will your Porsche if you hammer it day in and day out.

I am not suggesting that you leave it in the garage or not engage in spirited driving. Simply understand that trips to the rev limiter create a cost.

If this were NOT true, why would Porsche keep track of these trips for warranty purposes?

[MNBoxster]

Originally Posted by Brucelee

"The lack of revs(storing a car long enough for moisture to work it's magic)"

From the standpoint of engine longevity, this is probably not the correct way to frame it. I am certainly not suggesting you park your Porsche to preserve it.

I think the data shows that driving your Porsche to the red line on a daily basis will certainly shorten the drive train's life vs. a more prudent way of driving.

This is supported both in theory and in practice.

To wit, the useful life of just about any race car is very very short, even though these cars are built to specifically run at top RPMS (blue printed engines, forged metals, oil changes at every race etc.).

If running these cars at top RPM was "good for them" they would have a nice long lifespan.

They do not.

Nor will your Porsche if you hammer it day in and day out.

I am not suggesting that you leave it in the garage or not engage in spirited driving. Simply understand that trips to the rev limiter create a cost.

If this were NOT true, why would Porsche keep track of these trips for warranty purposes?

Hi,

I think your argument is somewhat superfluous. Your Race car analogy is somewhat off base as this is a car who's Engine differs in many ways to a Street Car Engine, such as in Compression, Timing, A/F mix, etc. Apples to Oranges. Besides that, a Race Car Engine is run about 75%-80% of the time at Red Line (if you plan on being Competitive), whereas we're only discussing occaisionally, or accidentally, bouncing off the Rev Limiter.

Lexuspilot has taken your logic to extreme, but he's not all wrong. Simply turning the key will eventually wear out the Engine. That's what Engine's do, they wear out, no matter how well you care for them, eventually all the heat and friction takes their toll.

I don't dispute that empirically you increase wear and/or shorten the Life of the Engine. But, you need to put some perspective to this. You may have a rebuild due at 100K rather than at 120k. That doesn't mean it's gonna Blow-up tomorrow.

Plus, there are many other ways of ignoring or abusing your Engine which will shorten it's life much sooner such as running low on fluids, buying Bad Gas, not allowing it to warmup sufficiently when it's cold, (which is probably the greatest sin committed - You know that little Blue mark on your temp gauge? You're supposed to allow the Temp Needle to travel North of it before driving, how many people do this consistently?).

No, I am not convinced that hitting the Rev Limiter, even on a consistent basis is much to worry about so long as you look after the car's Tune and Fluids. Every Engine I've ver seen Blow-up was from some other type of abuse, usually neglect.

Happy Motoring!...Jim'99

[Brucelee]

"No, I am not convinced that hitting the Rev Limiter, even on a consistent basis is much to worry about so long as you look after the car's Tune and Fluids. Every Engine I've ver seen Blow-up was from some other type of abuse, usually neglect."

I understand that you are not convinced and that is not my intention. You can drive your car off the rev limiter everyday and that is fine with me. However, it is factual that heat, friction and mechanical stress all act to increase wear in ANY engine, not matter how well maintained. Same applies to the drivetrain. So, all of these increase greatly as revs climb and the gas pedal goes rapidly to the floor.

As long as you understand that you are shortening your engine life, that is fine as it is your car.

Don't delude yourself into thinking that keeping your oil clean and plugs new is going to eliminate this "cost" as it will not. It will help but there is not cheating the man!

Also keep in mind that blowing up an engine and decreasing useful life are not necessarily the same thing. However, I would bet more engines "blow up" at red line than at 2500 rpms.

Lastly, if I understand your point about engine warm up correctly, it conflicts with every professional's advice that I have seen, which is to allow your cold engine to run about 10 seconds, drive off slowly and allow the engine to warm up quickly under light load.

AFTER the engine is fully warm, one can get more aggressive with driving.

If I understand what you are advocating, you would sit in the driveway until the temp gauges moves. Did I get that right?

If so, this theory went out with the 60s I believe.

[limoncello]

Continuing the debate -
Rail, IMHO, bouncing the rev limiter did no damage to your car.
Warm-up: Not as critical as it used to be, for starting and driving normally. I think the manual even says you can turn the key and go. As an old-schooler, I still let my cars idle for 5-10 seconds before I pull away - it's just habit. Here's the distinction: I never drive hard (aggressive throttle, or above 3500 RPM) until the car is FULLY warmed. If the car has been sitting for 3 weeks, I warm it up carefully.
High RPMs: Yes, continuous high RPMs (the race car) will burn up a motor quicker than all gentle driving. But sports cars, like Porsches, should be able to take 100,000 miles of driving by Porsche owners. Running the revs up smoothly on a regular basis should not burn the car up prematurely.
Smooth is a key word. Slamming the drivetrain wears out parts. (Many an SUV'er does damage to the soccer van by rolling backwards and dropping the automatic into drive while still moving backwards. That's bad.)
Porsche and the Economics of Warranty Work: The rev limiter is an easy target because it's measurable. It's easy to say that high RPMs = abuse. Sometimes that's correct, and sometimes it's not. Running the revs up smoothly is a joy, and personally, I don't think that alone should blow my motor early. (Track time might, however, which I do. Explains why I have a car that's out of warranty - no one would touch it after repeated trips to the track. If it breaks I'll fix it.) But Porsche is erring on their safe side - not surprising, they are a business enterprise. It's probably true that some drivers lose some deserved warranty work solely because they rev'd out a few times, but equally true that other owners wring the crap out of the cars and then take it to the dealer to fix it under warranty. And the SUV owner that puts it in drive while rolling backward gets their car fixed under warranty, simply because there is no strain gage on the driveshaft. Yet.
Back to Rail: IMO, no mechanical damage done, but your dealer may try to convince you otherwise at some future moment.

[Brucelee]

Lemon

As usual all good points.

According to my service shop, the computer tracks all overrevs.

This is not an automatic warranty no no.

However, if they see 50 or so of them,

Well........................

Good stuff.

[eslai]

Correlation versus causation, the usual logical fallacy! High engine revs can't be shown to *cause* premature engine failure, but there are other htings to take into account. If you're the type of driver that likes to drive the car hard, there's a lot of other stress factors involved than just how many times you revved the engine.

But even if there is a correlation, that doesn't make me comfortable with Porsche using computer data that states how many times you've hit [whatever] RPM as a tool for denying warranty claims. It is not proof of any sort that you've mistreated the car... well, except for really obvious over-revving of course...

[Brucelee]

Lets try this.

Does racing a car lengthen or shorten its useful life?

Do you want to buy a car that has been raced?

Does racing involve high revs and tremendous internal stresses?

Does daily trips to the redline lengthen or shorten an engines useful life?

Do manufacturer's in general have a qarranty disclaimer for racing or other forms of abuse?

Originally Posted by eslai

Correlation versus causation, the usual logical fallacy! High engine revs can't be shown to *cause* premature engine failure, but there are other htings to take into account. If you're the type of driver that likes to drive the car hard, there's a lot of other stress factors involved than just how many times you revved the engine.

But even if there is a correlation, that doesn't make me comfortable with Porsche using computer data that states how many times you've hit [whatever] RPM as a tool for denying warranty claims. It is not proof of any sort that you've mistreated the car... well, except for really obvious over-revving of course...