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Recommended Posts

Posted

Greetings:

I was viewing a Youtube video tonight showing a 997S going at a good clip...FAST! The speedo showed a red-line of 8000RPM. I think that the USA cars red-lining at 7400 rpm have been been governed respective of USA laws... any comments? I have had one experience of red-lining my 2006 997S and have had the limiter kick in... the dealer thought nothing of it...We in the US have been robbed of the true potential of our cars I thinkuth!!

Chromedome: North Couty San Diego

2006 997 S Carrara White Coupe. full leather sand interior etc......

Posted
Greetings:

I was viewing a Youtube video tonight showing a 997S going at a good clip...FAST! The speedo showed a red-line of 8000RPM. I think that the USA cars red-lining at 7400 rpm have been been governed respective of USA laws... any comments? I have had one experience of red-lining my 2006 997S and have had the limiter kick in... the dealer thought nothing of it...We in the US have been robbed of the true potential of our cars I thinkuth!!

Chromedome: North Couty San Diego

2006 997 S Carrara White Coupe. full leather sand interior etc......

That is one side of the argument. The other side is that Porsche set rev limit at 7400 on production cars to protect the wallet of the car owner. The cost of that sick sounding $20k Kaboom far outweighs the performance benefit of a couple hundred more revs. I am not sure how much useable performance they left on the table in the interest of reliability. It is always a tradeoff. After tossing a half dozen or so motors with no rev limit that grenaded due to overrev in the heat of battle I welcome a realistic rev limiter. It just reminds me to shift.

Now if you tear down the motor, fine balance the crank and cams, lighten pistons and rods, high rev valve springs, port polish balance and blueprint, increase top end lubrication, improve engine cooling, you will create some safety room for higher revs.

Just one mans opinion.

Posted
Greetings:

I was viewing a Youtube video tonight showing a 997S going at a good clip...FAST! The speedo showed a red-line of 8000RPM. I think that the USA cars red-lining at 7400 rpm have been been governed respective of USA laws... any comments? I have had one experience of red-lining my 2006 997S and have had the limiter kick in... the dealer thought nothing of it...We in the US have been robbed of the true potential of our cars I thinkuth!!

Chromedome: North Couty San Diego

2006 997 S Carrara White Coupe. full leather sand interior etc......

That is one side of the argument. The other side is that Porsche set rev limit at 7400 on production cars to protect the wallet of the car owner. The cost of that sick sounding $20k Kaboom far outweighs the performance benefit of a couple hundred more revs. I am not sure how much useable performance they left on the table in the interest of reliability. It is always a tradeoff. After tossing a half dozen or so motors with no rev limit that grenaded due to overrev in the heat of battle I welcome a realistic rev limiter. It just reminds me to shift.

Now if you tear down the motor, fine balance the crank and cams, lighten pistons and rods, high rev valve springs, port polish balance and blueprint, increase top end lubrication, improve engine cooling, you will create some safety room for higher revs.

Just one mans opinion.

Greetings:

I have heard this argument before... that being that you gain very little from having the rpm range extended at the top end. I don't have a problem with a rev limiter.. I look it as a great thing...with the laws as they are in California you get thrown in jail for going even 1 mph over 100mph, and there are those infractions which cover " unsafe " or " exhibition of speed " driving. The vast majority of us will never experience the true potential of the 997. My point would be that if you extend the rpm range at the top you also extend it in the middle , would it not be logical that the performance ( generally ) would also be increased, in the middle. I've always wondered why BMW governs my 2004 5 series at 155mph.... I don't think the Germans would react with glee if it was done to German cars. As far as the " motor tear down ", I really hope Porsche did at least a few of those things before they assembled my engine... for $99,949.85 out- the - door.. I would expect it.

Chromedome

2006 997 C2S, Carrara White, full leather ec.....

Posted
Greetings:

I was viewing a Youtube video tonight showing a 997S going at a good clip...FAST! The speedo showed a red-line of 8000RPM. I think that the USA cars red-lining at 7400 rpm have been been governed respective of USA laws... any comments? I have had one experience of red-lining my 2006 997S and have had the limiter kick in... the dealer thought nothing of it...We in the US have been robbed of the true potential of our cars I thinkuth!!

Chromedome: North Couty San Diego

2006 997 S Carrara White Coupe. full leather sand interior etc......

That is one side of the argument. The other side is that Porsche set rev limit at 7400 on production cars to protect the wallet of the car owner. The cost of that sick sounding $20k Kaboom far outweighs the performance benefit of a couple hundred more revs. I am not sure how much useable performance they left on the table in the interest of reliability. It is always a tradeoff. After tossing a half dozen or so motors with no rev limit that grenaded due to overrev in the heat of battle I welcome a realistic rev limiter. It just reminds me to shift.

Now if you tear down the motor, fine balance the crank and cams, lighten pistons and rods, high rev valve springs, port polish balance and blueprint, increase top end lubrication, improve engine cooling, you will create some safety room for higher revs.

Just one mans opinion.

Greetings:

I have heard this argument before... that being that you gain very little from having the rpm range extended at the top end. I don't have a problem with a rev limiter.. I look it as a great thing...with the laws as they are in California you get thrown in jail for going even 1 mph over 100mph, and there are those infractions which cover " unsafe " or " exhibition of speed " driving. The vast majority of us will never experience the true potential of the 997. My point would be that if you extend the rpm range at the top you also extend it in the middle , would it not be logical that the performance ( generally ) would also be increased, in the middle. I've always wondered why BMW governs my 2004 5 series at 155mph.... I don't think the Germans would react with glee if it was done to German cars. As far as the " motor tear down ", I really hope Porsche did at least a few of those things before they assembled my engine... for $99,949.85 out- the - door.. I would expect it.

Chromedome

2006 997 C2S, Carrara White, full leather ec.....

Most of those refinements can be found on the X51 motor with a corresponding increase in rev limit and price tag.

  • 2 months later...
Posted

The HP and torque are not linear. They don't just keep going up as the engine winds up to max. And you don't want the car to hit the rev limiter anyway. It disturbs the car balance.

Posted

A red line limiter and a velocity governor are different things. The BMW limits velocity probably because of safety considerations (lawyers?), maybe because even Z rated tires are not speced at higher speeds. Possibly that's a US only legal issue for BMW.

I am pretty sure that the Carrera red line is the same in cars sold in Germany as in the US. It is meant to protect the engine from blowing up, not to limit your speed.

The 6th gear limit corresponds to about 178 MPH (depending on model) and I doubt the cars have the horsepower to push air at much higher speeds. The power required goes as the cube of the velocity to move through the air. It takes 15% more HP (around 50 HP more) to push the car at 178 than at 170 MPH! (See http://en.wikipedia.org/wiki/Drag_(physics)) So you would need lots of time on a very flat, windless, road to have a prayer of getting close to the red line in 6th gear.

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