RPM for Everyday Driving

[rdancd816]

[QUOTE=RandallNeighbour]Here's a non-technical answer since Jim did an excellent job of that...

Hey Randall, I like you drive a '97 2.5. I am curious as to what temp you read when the car is warm? I tend to shift at very similar tach points as you. Since the car has such low miles I'm almost following the break-in recommendations. Just curious abut what your temp guage says. Mine seems to settle a bit above the 180 line. BTW just touched 13,000 miles and so far all is well. I've put about 3500 on it since purchase.

[blinkwatt]

[QUOTE=rdancd816]

Originally Posted by RandallNeighbour

Here's a non-technical answer since Jim did an excellent job of that...

Hey Randall, I like you drive a '97 2.5. I am curious as to what temp you read when the car is warm? I tend to shift at very similar tach points as you. Since the car has such low miles I'm almost following the break-in recommendations. Just curious abut what your temp guage says. Mine seems to settle a bit above the 180 line. BTW just touched 13,000 miles and so far all is well. I've put about 3500 on it since purchase.

Anywhere along the 180 line is normal,it can go slighty above that during summer. Anything higher requires a radiotor cleaning and coolant check. If that doesnt help then a trip to the dealer is required.

[rdancd816]

I think I'll get it checked. Thanks for the reply. Car runs fine but the reading seemed a bit hot for 70 degree weather. Trunk floor is dry so I don't think the coolant tank is bad. Paranoid probably, but an ounce of prevention is worth a pound of cure! Old Boxster owners die hard!

[SD987]

There's the theoretical and the practical side of the question and since the title of this post was "RPM for every day driving" I think the practical side makes much of this boy-racer discussion, academic.

In the 987 with the 5 speed, 6500 rpms will get you:

1st @ 33 mph
2nd @ 63 mph
3rd @ 93 mph

Unless you routinely get up to 100 mph everyday let's keep the discussion around 1st and 2nd gear. The whole point of redlining the engine as MNBoxster notes would be to achieve a higher speed as quickly as possible, but it's my experience that redline driving doesn't match real world driving conditions (although I wish it did).

In the world I live in, there's frequently someone driving a car in front of me; most folks drive in a band between 35 - 55; you're only first in line at the traffic light maybe 20% of the time (if you try to be); there's usually a nun who steps into the crosswalk without looking; it's 2:30pm once a day so you're in a school zone now; there's often a cop at the next intersection; everybody starts to slow down while you're speeding up cuz there's an accident or some hot chick is waiting to cross the street....yada yada yada.

So you can consider whether you'll be routinely shifting at 6500 rpms when you get out of your break-in period but I can tell you that you won't be and you won't want to...unless you live in a world where:

People wave to you just cuz they're happy to make human contact; traffic lights or stop signs are separated by miles; you're a nun-killer without regard for innocent children just trying to learn and make the world a better place (they're only children...why do you have to try and scare them with your 2.7 litres of horizontally-opposed fury?) your brother's on the police force; no one ever crashes their car in your municipality of homely women...yada yada yada.

More than the shift point, I think the more pertinent question for engine wear would be what RPMs do people routinely sustain at speed rather than during acceleration? If you think it's prudent to cruise @ 60 mph in 2nd gear or drive through that school zone at the redline knock yourself out, but in general I think shifting at or sustaining near-redline RPMs would be hard to characterize as anything but recreational and occasional. In general your own common sense and local vehicular code will prevent you from doing much damage to yourself or your car and the occasional opportunity you'll have to really rev that engine is well within the tolerances that Porsche has engineered.

[RandallNeighbour]

rdancd816:

My temp needle used to remain between the 1 and the 8 in "180". In bad traffic, it rose to right of the zero, and I discovered one of my radiator fans had burned out.

You should check to see if your fans are working before you take it in. When the car is fully heated up after a spirited drive, park it in idle, turn on the AC real low, and get out of the car and put your hand under the front bumper, just in front of both wheels.

You should feel a blast of hot air from both sides. The driver's side is the primary radiator and the passenger side is the secondary, which usually starts up under an AC load.

If one or the other isn't working, this may be the reason behind your needle moving up and you'll be able to gauge the costs involved (the part cost me $175 and the labor was 2 hours. Stealership wanted $650 but I cheated the man once again). I temper this statement with the fact that my car's cooling system is working well and not leaking, and sitting in traffic does raise the needle a bit, but not much. Certainly within operating range... and Houston's outrageously hot most of the year.

Today, my needle sits squarely on the line marking 180 to the left of the numbers... probably a bit lower than it should be. That's because I swapped gauge faces and getting those needles back exactly where they belong is an artistic talent I do not possess. Search on my gauge face thread for all the gorey, frustrating details.

[eslai]

I find little reason to rev higher than 5000 RPM unless I'm really out for a sprint. Coming out of the northbound I-15 onramp at Mira Mesa Blvd. in San Diego, from eastbound on Mira Mesa Blvd. is an example of where one might hold revs up to redline-- it's a big, wide "clover leaf"-style right-hander, ending in a new, empty lane.

[Brucelee]

Originally Posted by eslai

I find little reason to rev higher than 5000 RPM unless I'm really out for a sprint. Coming out of the northbound I-15 onramp at Mira Mesa Blvd. in San Diego, from eastbound on Mira Mesa Blvd. is an example of where one might hold revs up to redline-- it's a big, wide "clover leaf"-style right-hander, ending in a new, empty lane.

I think this is very sound advice. Frankly, "bouncing the car off the rev limiter" is for folks who have PLENTY of cash to spare. Moreover, for you guys under warranty, porsche keeps the data on the rev limiter and will use it to deny warranty repairs if they are in the mood.

That latter issue is a fact, I have seen it happen.

If one looks at the HP and torque CURVES of the Box, that bad boy starts to flag as it approaches 6000 I believe.

Running past there is more an exercise in ego than anything else. But, it is your car and your license.

Isn't freedom wonderful!

[denverpete]

[QUOTE=rdancd816]

Originally Posted by RandallNeighbour

...Mine seems to settle a bit above the 180 line....

Mine does exactly the same thing. While dead center on 180 is what the manual states, mine has always been slighting above that regardless of warm weather or hard driving. Just figure that's normal for your car and gauge. Now, if it deviates drastically from that - then you've got a problem.