Keep her above 4000rpm and she'll thank you for it every day.

[Paul]

Unless you are going to keep your car for 150,000 to 200,000 miles, who cares?

With just the Porsche recommended maintenance you can drive these cars hard for at least that long.

It's a toy, enjoy it!

[rule1]

Should you run your car over 4000 rpm before its warmed up?

[Frodo]

I'd venture a "Negative" on that one.

Don't know a heck of a lot on the matter, but my gut tells me (and I follow it!) to keep her down at not much (if any) over 3000 RPM until warmed up (180 on the temp gauge). So far so good.

[blue2000s]

Originally Posted by rule1

Should you run your car over 4000 rpm before its warmed up?

Check out my link above, there is a strong relationship between engine wear and oil temperature. Warm up that engine before loading it!

[LoveBunny]

I've been told that you shouldn't go above a certain RPM for a certain amount of miles on a new car. Is that true?

[renzop]

BruseLee - The racecar analogy is lame and inaccurate. Stop using it. True race engines are built for top performance, not reliability or longevity. They are higher compression, have aggresive cam profiles, have aggressive timing. Run low additive high octane fuels, have astronomical red lines. All this leads to more HP and short life. It is not just running at high RPM that makes them grenade.

[Brucelee]

Originally Posted by renzop

BruseLee - The racecar analogy is lame and inaccurate. Stop using it. True race engines are built for top performance, not reliability or longevity. They are higher compression, have aggresive cam profiles, have aggressive timing. Run low additive high octane fuels, have astronomical red lines. All this leads to more HP and short life. It is not just running at high RPM that makes them grenade.

The analogy is still apt. At what RPM do these guys make all that HP? Well, up near red line.

Read the title of the thread again. The contention here is that running your box up at very high RPMs is GOOD FOR THE CAR!

That simply can't be substantiated by good physics or engineering.

It might be good for the driver (it is very much fun) but I simply don't like sloppy thinking.

I am not suggesting anyone drive around town and lug the motor nor not run the car at whatever RPM they want.

I am suggesting that they get real. Running the car at 5000 RPM plus is not doing your engine a world of good. It is not a muscle, it does NOT get stronger with use.

[Brucelee]

Posted by NITRO on July 03, 1998 at 09:24:41:

In reading your question, you have answered it with your research.


Regarding friction and wear, once again, you answered the question. If pistons travel at higher speed/ crank revolution, the amount of wear is greater. The anti friction composites we're now using help some, but T.O.O. also has another saying: Everything mechanical will eventually wear out and break.


The most common rod failures we've experienced over the years have always taken place on the "overlap" cycle, where the piston is traveling up at high velocities, with no compression up-top, and when the rod tries to slow the piston as it nears TDC, the rod goes, the piston pin can go, and the pin will sometimes pull the bosses out of the piston, or all of the above.


You're (simply) dealing with Mass x Velocity (squared). Now, examine the figures. Both mass and velocity are the players, but wich one is squared? = Velocity.
Regardless of rod ratio or any other player, the greater the RPM the higher the velocities, which = "ruined peoples motors".
What you like (regarding high rpm power), and what your engine likes are two different things.

If you ask any engine in the world if it enjoys running at high rpm = max. Q or stress, everyone of them will tell you they don't like it, unless one has a death wish or something.

T.O.O.'ll probably be around to better answer your question, but I gaurantee that he'll touch on the same items, and he talks to engines as well, that's how he makes them do what he wants, although he does write their genetic codes in the pre-build engineering.



--------------------------------------------------------------------------------

RPM's are nice...they are our friend

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Posted by 82'Rolla on July 03, 1998 at 06:21:24:

I love the sound of a high revver as well. Unfortunately to make your engine do this, it must be very well guarded against the added stress.


"*Maximum piston acceleration is approximately 8,000g which
puts a load of over 3 tons on each connecting rod."

This is where a lot of the damage comes from, and it increases non-linearly, not sure if it's exponential, plus the fact that the piston actually travels further. The stresses that your engine endures by raising the rpm's by 1000rpms is much worse than increasing boost by 10psi.


I suppose if you start out with the intentions of building a high revver, and compensate accordingly, it can be reliably done, but it sure will get expensive...Carillo rods ain't cheap.

I think it was Louis (deVirgilio sp?)from honda-perf who was also looking at this at some time, and noted the differences in the internal construction of the engines in relation to it's revability.Posted some nice articles, I think I still have them.

Ted

[Brucelee]

Ecopower
The Valtra N111 EcoPower model offers fuel savings of 10-15 percent by lowering the engine speed. The average piston speed is 20 percent
slower than in regular engines. The lifespan of the engine is correspondingly extended. Wet cylinder liners and intercooling also extend the lifespan of
SisuDiesel engines. In practice, the Valtra N111 EcoPower model means significantly lower workhour costs, environmental friendliness and low
emissions. An added benefit is the reduction in engine noise by 4-5 decibels.

Originally Posted by LoveBunny

I've been told that you shouldn't go above a certain RPM for a certain amount of miles on a new car. Is that true?

LB, very true. The Porsche owner's manual does a very good job telling owners how to brake-in a new car & engine.

<4,200 RPM's for the first 2,000 miles is the "key" one.

[Brucelee]

Originally Posted by bmussatti

LB, very true. The Porsche owner's manual does a very good job telling owners how to brake-in a new car & engine.

<4,200 RPM's for the first 2,000 miles is the "key" one.

My prediction: a post will arrive shortly telling us that the proper way to break in an engine is to "drive it like you stole it." They will support that with "my friend is an engine builder" story.

These posts CAN get somewhat predictable.


BTW- the advice on limiting revs on break in has been around since I was a kid, a very long time indeed.

Must be somthing to it. hard to believe the car makers want to have their engines inplode.

[RandallNeighbour]

Originally Posted by Paul

Unless you are going to keep your car for 150,000 to 200,000 miles, who cares?

Please remind me never to buy a used Porsche from you

I am planning to keep my car well past 200,000 miles as I cannot afford a newer or new one. So this attitude doesn't work for me from any angle.

Originally Posted by Paul

With just the Porsche recommended maintenance you can drive these cars hard for at least that long... It's a toy, enjoy it!

My 2.5 motor only lasted 79k, and measuring the condition of the car when I got it at 82k, those were 79k hard miles. It appears that all the maintenance was done on the car too from records I've come across. The new motor (not reconditioned) that was put in the car and only had a couple of thousand miles on it now has 25k after three years of spirited weekend driving.

I replaced the tranny two years ago for suspect noises in 1st and 2nd gear at low rpm.

I would not be surprised if during my ownership of this car, with meticulous maintenance and replacement of every single thing I can find that is wearing or worn, I will have to put a third motor in it. Of course, it will be a 3.4 or 3.6, but nevertheless, I might not get 200k out of this new motor with the intermediate shaft failures that still occur in newer Porsche engines.

Paul, you have a good attitude about your car... it is indeed a rich man's toy for sure!
I drive my car like I stole it a lot of the time and run it up to redline most every time I put the key in the ignition. I just don't keep it above 4,000 rpm all the time because I want to keep my existing motor running for at least another 100,000 miles.

I think there's two schools of thought about sports car ownership. Those like yourself who enjoy the car to its full limits and might be harder on the motor than one who buys a car to own for 20+ years. I'm that second kind of guy by virtue of my personal financial situation and my growing satisfaction of fixing up an old car that has my fingerprints on most every part of the car as the years go by.

I guess my take on this thread is this: The motor is designed to be revved right up to redline and it does blow carbon out of the motor ... and the sound is glorious at redline. Conversely, if one keeps the revs up all the time, he or she will be replacing the motor sooner than later.

[Paul]

Originally Posted by RandallNeighbour

Paul, you have a good attitude about your car... it is indeed a rich man's toy for sure!

I drive my car like I stole it a lot of the time and run it up to redline most every time I put the key in the ignition. I just don't keep it above 4,000 rpm all the time because I want to keep my existing motor running for at least another 100,000 miles.

I agree and do the same except I see no issue with running the car above 4000 rpms IF IT"S IN TOP GEAR (in my case 5th).