What makes the .2 "S" so freakin' fast?
#31
06-01-2009, 05:58 PM
Join Date: Apr 2004
Location: North Dakota
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deputy,
My 997s.1 weighs in @ 3025. This is on my registration. Now, either they weigh it wrong, or Porsche is not being truthful with the real weight of the 997?
Unless your friends car is a ringer or weight is well under the official weight, his car should not beat yours. When was the last time you tuned your set up again? Maybe it's not running at it's optimal since the last time you tuned it?
My 997s.1 weighs in @ 3025. This is on my registration. Now, either they weigh it wrong, or Porsche is not being truthful with the real weight of the 997?
Unless your friends car is a ringer or weight is well under the official weight, his car should not beat yours. When was the last time you tuned your set up again? Maybe it's not running at it's optimal since the last time you tuned it?
I haven't dyno'd my car in a while, but my boost gauge still says I'm still making 5 psi (which is normal) and I've had new plugs installed within the past 6 months.
#32
06-01-2009, 06:00 PM
Join Date: Apr 2004
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I ran him from 2nd through the top of 3rd a while back. Pretty much the exact same results.
Whatever the reason, this new 997S is one hell of a car!
Whatever the reason, this new 997S is one hell of a car!
#33
06-01-2009, 06:04 PM
One thing I never really understood was why people spend thousands of dollars on something like carbon fiber pieces and don't get all kinds of features JUST to save weight, and yet, when they go to do a 1/4 mile or track the car, they leave all the seats in, spare tires, have a passenger ride along, full tank of gas, etc. There should be laws against cars with carbon fiber parts having spare wheels.
#34
06-01-2009, 06:08 PM
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Rep Power: 122 What size or your rear tires?
#35
06-01-2009, 06:16 PM
Join Date: Apr 2004
Location: North Dakota
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Rep Power: 502 Did you consider things like tires, passengers, mods that reduced drag coefficients, etc?
One thing I never really understood was why people spend thousands of dollars on something like carbon fiber pieces and don't get all kinds of features JUST to save weight, and yet, when they go to do a 1/4 mile or track the car, they leave all the seats in, spare tires, have a passenger ride along, full tank of gas, etc. There should be laws against cars with carbon fiber parts having spare wheels.
One thing I never really understood was why people spend thousands of dollars on something like carbon fiber pieces and don't get all kinds of features JUST to save weight, and yet, when they go to do a 1/4 mile or track the car, they leave all the seats in, spare tires, have a passenger ride along, full tank of gas, etc. There should be laws against cars with carbon fiber parts having spare wheels.
We were both coming home from the weekend at the track so we had the same amount of luggage and misc junk. We also filled up at the same time so our tanks should have been even.
#36
06-01-2009, 06:19 PM
Join Date: Apr 2004
Location: North Dakota
Posts: 9,541
Rep Power: 502 Then something is wrong with your setup. There is no way a stock 997S should have pulled you. Maybe you're pulling timing. Disconnect the battery for a few seconds. Then take it our for a sprint. If your timing was being pulled, you'll know it.
What size or your rear tires?
What size or your rear tires?
You may be right. I'll try the battery disconnect. Maybe I need to get it over for a dyno run as well. AF and boost seem to be normal so I'm not sure why the car would be pulling timing. I run 93 octane and the temps weren't abnormally hot outside. Why do you think it would be pulling timing?
Right now I'm running 285-35-19.
#37
06-01-2009, 06:24 PM
What is the weight of a .2 S model? I'm just guessing that it's probably 3250??
The transmission, from what I can tell, played no roll in this. We were at approx 50 mph. He selected a gear he was comfortable with and I did the same. These were simple highway roll ons. What I don't understand is that if you overlaid our dyno charts I can pretty much guarantee I'm making more power (HP and TQ) everywhere.
Help me understand this... As I said before, I've run a lot of other cars. It was fairly predictable based on their HP. This just makes no sense.
The transmission, from what I can tell, played no roll in this. We were at approx 50 mph. He selected a gear he was comfortable with and I did the same. These were simple highway roll ons. What I don't understand is that if you overlaid our dyno charts I can pretty much guarantee I'm making more power (HP and TQ) everywhere.
Help me understand this... As I said before, I've run a lot of other cars. It was fairly predictable based on their HP. This just makes no sense.
If you aren't pulling timing...than I think that Ced’s right. It's more than likely primarily due to the area under the curve. I believe you are running a centrifugal S/C on your car, which makes most of its power at higher rpm….but not a whole lot at lower rpm. Its area under the curve that wins races, not peak HP.
A good example of this is the Corvette Z06. A head/cam/bolt-on N/A Z06 making 550 rwhp is typically as fast or faster than most centrifugal S/C’s Z06's with 50-100 more rwhp...due to where and when the N/A car makes it torque….and the large area under the curve. So even though the peak HP #’s on the S/C car are much higher, it doesn’t translate into commensurate acceleration increases. The new 997.2 is obviously a properly hopped up N/A motor, so the way it makes its power in comparison to your car may be the difference.
This is the primary reason I went with a roots-style S/C on my car, which makes power almost exactly the same as a N/A motor does (plenty of torque early on), but just with a LOT more power.
That said; I'd really like to see a dyno graph of your car, that could answer a lot of questions.
Another thing to consider is that S/C cars lose more power than N/A cars due when running due to heat soak. Heat may have closed the HP delta between the two of you more than you would have imagined.
As far as the weight of the two cars, unless you guys are racing from a dead stop, it isn’t nearly as important as the area under the curve is. I believe this is a power/curve issue...not a weight issue.
Last edited by Divexxtreme; 06-01-2009 at 06:30 PM.
#38
06-01-2009, 06:24 PM
He's got PS2's. I've got Dunlops. No passengers in either car. His car is bone stock. My car has a techart wing and a turbo front bumper.
We were both coming home from the weekend at the track so we had the same amount of luggage and misc junk. We also filled up at the same time so our tanks should have been even.
We were both coming home from the weekend at the track so we had the same amount of luggage and misc junk. We also filled up at the same time so our tanks should have been even.
#40
06-01-2009, 06:34 PM
The only thing I can think of aside from that is the fact that you're relying on turbos for HP and he isn't. Turbos are an odd creature, heavily dependent on a whole bunch of things. There is a reason why they typically leave the turbos out of high performance cars - they make for great numbers but when push comes to shove and you hit the pedal, there's not telling what they will do.
#42
06-01-2009, 06:58 PM
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If you aren't pulling timing...than I think that Ced’s right. It's more than likely primarily due to the area under the curve. I believe you are running a centrifugal S/C on your car, which makes most of its power at higher rpm….but not a whole lot at lower rpm. Its area under the curve that wins races, not peak HP.
A good example of this is the Corvette Z06. A head/cam/bolt-on N/A Z06 making 550 rwhp is typically as fast or faster than most centrifugal S/C’s Z06's with 50-100 more rwhp...due to where and when the N/A car makes it torque….and the large area under the curve. So even though the peak HP #’s on the S/C car are much higher, it doesn’t translate into commensurate acceleration increases. The new 997.2 is obviously a properly hopped up N/A motor, so the way it makes its power in comparison to your car may be the difference.
This is the primary reason I went with a roots-style S/C on my car, which makes power almost exactly the same as a N/A motor does (plenty of torque early on), but just with a LOT more power.
That said; I'd really like to see a dyno graph of your car, that could answer a lot of questions.
Another thing to consider is that S/C cars lose more power than N/A cars due when running due to heat soak. Heat may have closed the HP delta between the two of you more than you would have imagined.
As far as the weight of the two cars, unless you guys are racing from a dead stop, it isn’t nearly as important as the area under the curve is. I believe this is a power/curve issue...not a weight issue.
If you aren't pulling timing...than I think that Ced’s right. It's more than likely primarily due to the area under the curve. I believe you are running a centrifugal S/C on your car, which makes most of its power at higher rpm….but not a whole lot at lower rpm. Its area under the curve that wins races, not peak HP.
A good example of this is the Corvette Z06. A head/cam/bolt-on N/A Z06 making 550 rwhp is typically as fast or faster than most centrifugal S/C’s Z06's with 50-100 more rwhp...due to where and when the N/A car makes it torque….and the large area under the curve. So even though the peak HP #’s on the S/C car are much higher, it doesn’t translate into commensurate acceleration increases. The new 997.2 is obviously a properly hopped up N/A motor, so the way it makes its power in comparison to your car may be the difference.
This is the primary reason I went with a roots-style S/C on my car, which makes power almost exactly the same as a N/A motor does (plenty of torque early on), but just with a LOT more power.
That said; I'd really like to see a dyno graph of your car, that could answer a lot of questions.
Another thing to consider is that S/C cars lose more power than N/A cars due when running due to heat soak. Heat may have closed the HP delta between the two of you more than you would have imagined.
As far as the weight of the two cars, unless you guys are racing from a dead stop, it isn’t nearly as important as the area under the curve is. I believe this is a power/curve issue...not a weight issue.
At 50 mph Dog's engine is at 5,000 rpm which is it's best point in the power curve, making substantially more compression than the 997S. He also has an aftercooler, which, if the pump is running, all but eliminates heat soak. There would have to be a 500+ pound difference between cars for the 997S to have a chance.
#43
06-01-2009, 07:28 PM
At 50 mph Dog's engine is at 5,000 rpm which is it's best point in the power curve, making substantially more compression than the 997S. He also has an aftercooler, which, if the pump is running, all but eliminates heat soak. There would have to be a 500+ pound difference between cars for the 997S to have a chance.
#45
06-01-2009, 07:36 PM
Join Date: Apr 2004
Location: North Dakota
Posts: 9,541
Rep Power: 502 A highway run might be fun though
