Trak Car v.3 in Good Hands
06-15-2012, 07:53 PM
#34
Addict
Rennlist Member
Rennlist Member
@DeputyDog
Your biggest time loss is on the sections where no skills are necessary (other than resetting the braking marks), on the straights.
I define a straight, as any section where I can drive full gas. At Daytona, the entrance to the bowl until the bus stop is a straight (it looks like a turn).
Sebring has the following straights:
T17-T1
T1-T3
T5-T7
T7-T10
T10-T13
T13-T15
T15-T16
T16-T17
In certain powerful cars, T13-T15 is not a straight, neither is T10-T13 in the sense that full gas cannot be used.
In the dyno chart below courtesy of Sharkwerks, I have highlighted the range of power with your shifting and the range of power with better use of the engine. I'm using the 3rd to 4th gear upshift with the 997.1 GT3 gearing (which is the same gear set as all the 997.1 and 997.2 GT3/RS for 3rd and 4th). The Blue line is power to the wheels with a stock 997.1 GT3 (like yours) or 997.1 GT3 RS. The Red bars determine your power curve with your shifting and the Green bars determine the power curve with better use of the engine.
You short shift at full gas from 3rd to 4th, you seem to do it at 7200 rpm most of the time with erratic ones as low as 6900rpm and as high as 7500 based on your videos, but your average is 7200rpm. When your car enters 4th gear, it will be producing just a little over 300whp. The driver swinging the car to 8400rpm in 3rd gear will land 4th gear at 6600rpm, while you landed at 5700rpm. At 6600 rpm the same car is producing 350whp.
If we use power loses of just 6%, you're driving a GT3 in 4th gear with 320 HP, while the other driver swinging the engine at higher RPM will be at 370HP. This is a difference of 50Hp.
How big is a difference of 50HP? Well, it is the difference between the 4.0RS and the 3.8RS and I have seen how the 4.0RS walks away from the 3.8RS. By the way, the 50Hp more powerful 4.0RS is about 2 secs faster at Sebring, and the gains are on power mostly, handling is almost identical.
On your next track event, do a session shifting at 7200rpm max, then another session shifting at 8400rpm, compare lap times, and if the track is Sebring, you should see a 1.5 secs average difference in lap times.
...ok now I need to modify the Coxster.
Your biggest time loss is on the sections where no skills are necessary (other than resetting the braking marks), on the straights.
I define a straight, as any section where I can drive full gas. At Daytona, the entrance to the bowl until the bus stop is a straight (it looks like a turn).
Sebring has the following straights:
T17-T1
T1-T3
T5-T7
T7-T10
T10-T13
T13-T15
T15-T16
T16-T17
In certain powerful cars, T13-T15 is not a straight, neither is T10-T13 in the sense that full gas cannot be used.
In the dyno chart below courtesy of Sharkwerks, I have highlighted the range of power with your shifting and the range of power with better use of the engine. I'm using the 3rd to 4th gear upshift with the 997.1 GT3 gearing (which is the same gear set as all the 997.1 and 997.2 GT3/RS for 3rd and 4th). The Blue line is power to the wheels with a stock 997.1 GT3 (like yours) or 997.1 GT3 RS. The Red bars determine your power curve with your shifting and the Green bars determine the power curve with better use of the engine.
You short shift at full gas from 3rd to 4th, you seem to do it at 7200 rpm most of the time with erratic ones as low as 6900rpm and as high as 7500 based on your videos, but your average is 7200rpm. When your car enters 4th gear, it will be producing just a little over 300whp. The driver swinging the car to 8400rpm in 3rd gear will land 4th gear at 6600rpm, while you landed at 5700rpm. At 6600 rpm the same car is producing 350whp.
If we use power loses of just 6%, you're driving a GT3 in 4th gear with 320 HP, while the other driver swinging the engine at higher RPM will be at 370HP. This is a difference of 50Hp.
How big is a difference of 50HP? Well, it is the difference between the 4.0RS and the 3.8RS and I have seen how the 4.0RS walks away from the 3.8RS. By the way, the 50Hp more powerful 4.0RS is about 2 secs faster at Sebring, and the gains are on power mostly, handling is almost identical.
On your next track event, do a session shifting at 7200rpm max, then another session shifting at 8400rpm, compare lap times, and if the track is Sebring, you should see a 1.5 secs average difference in lap times.
...ok now I need to modify the Coxster.
Last edited by NJ-GT; 08-13-2013 at 10:18 AM.
06-16-2012, 03:58 PM
#35
Race Director
