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What are we trying to figure out? The top speed for each gear? There is only 1 way to find out (and experience) what your car actually does, not the formula
Can't tell if you're serious or not, but, the math is the math.
In reality, what your speedo indicates on the road is not technically 100% accurate since there are variables the programming of the vehicle cannot account for... ie: if the tires have worn down and have now, even if just ever-so-slightly, changed the total rolling diameter from when they were new.
And, then, of course, most speedo's are off by a few percent from the factory regardless. It's actually a handy technicality for getting out of speeding tickets
Im dead serious. Youre 100% correct math doesnt lie. Just would like to experience the stats rather than paper race myself in my garage, lol. Im totally guilty of having done this in the past. And i plan on using a 50 hz gps and a 10hz gps simultaneously.
Im dead serious. Youre 100% correct math doesnt lie. Just would like to experience the stats rather than paper race myself in my garage, lol. Im totally guilty of having done this in the past. And i plan on using a 50 hz gps and a 10hz gps simultaneously.
Oh, that's fine if you want to go to that level of trouble. Personally, I just don't find enough opportunities to take the car to redline, let alone try to document it in real time. If I'm lucky I might get to redline 1st gear once per drive, 2nd, maybe once... never 3rd since the gearing on these cars is so ridiculously tall that you're at car-impoundment speeds if you go to the top of third.
The one I saw had not just the transmission curves, but rated power & torque at each shift point overlaid, so one could easily observe optimal shift points for various speeds...now I'm wondering if someone posted it from one of the media events pre-launch...
Also, because of the smaller volume turbos, peak power is much before redline, so no reason to redline to get best performance.
To compare, the GTS peak power is later in rev range with its larger turbos.
Also, because of the smaller volume turbos, peak power is much before redline, so no reason to redline to get best performance.
To compare, the GTS peak power is later in rev range with its larger turbos.
Hmm the GTS make more power all the time - hence 550Nm Vs 450Nm.
Also, because of the smaller volume turbos, peak power is much before redline, so no reason to redline to get best performance.
To compare, the GTS peak power is later in rev range with its larger turbos.
I thought peak ho and torque numbers were the same rpm as the base, you just get it a little sooner (time wise).
Thick red line = acceleration curve and optimal performance gear change points
Thick black line = engine HP peak.
Basically this give the T a 4.3% increase in wheel torque over the base.
This is awesome info and thank you for posting. Just curious how this is determined and what does "optimum" mean - so i understand? Is it for fastest acceleration or best for matching the revs?. Shifts from 1-2-3 are in the peak torque band but not above 4. Just curious if you ring out the first 3 gears to 6500-7000 whether this will be slower than shifting at the optimal shiftpoints shown above
This bit is the important piece of information "Basically this gives the T a 4.3% increase in wheel torque over the base."
This is why I'd love to see someone offer a more aggressive final drive. I want to change gears more often, and I want that mechanical torque advantage!
This is awesome info and thank you for posting. Just curious how this is determined and what does "optimum" mean - so i understand? Is it for fastest acceleration or best for matching the revs?. Shifts from 1-2-3 are in the peak torque band but not above 4. Just curious if you ring out the first 3 gears to 6500-7000 whether this will be slower than shifting at the optimal shiftpoints shown above
In almost all circumstances, it pays to shift at the redline. The way to look at it is to see what hp the engine is making in your current gear and current rpm and then see what it would be making in the next gear after you upshifted.
For example, if you wind a base 911 or T to the 7400 rpm redline in 1st gear, the engine, at that point, is making 350 hp. When you shift to 2nd, the revs drop to about 4400 rpm, where the engine is only making 285 hp, so it would have been better to shift at even higher rpm, except that the rev limiter wouldn't let you.
As you go through the gears and the gear spacing gets closer, this effect is reduced, but here are the numbers for the other gears:
2nd gear at 7400/350 hp, after shift to third, 5100 rpm/325 hp
3rd gear at 7400/350 hp, after shift to 4th, 5600 rpm/345 hp. Shifting at the redline is still paying off.
4th gear at 7400/350 hp, after shift to 5th, 6000 rpm/355 hp. So here, it would have been better to shift a bit sooner:
4th gear at 7000/355 hp, after shift to 5th, 5600 rpm/345 hp. Perhaps 7200 would be best:
4th gear at 7200/360 hp, after shift to 5th, 5800 rpm//360 hp. Perfect.
5th gear at 7200/360 hp. after shift to 6th, 6000 rpm/355 hp. Pretty good.
These numbers are approximations taken from the gearing chart and power curve, and the could be off a hundred rpm here and there, but you get the idea. I don't know what those "optimum shift points" represent, but they have nothing to do with maximizing acceleration.
07-26-2018 | 09:26 PM
