Coasting- seriously, for real?
12-06-2017, 08:11 PM
#61
Agreed and this is less than all of the other cars Matt posted save the 800 hp. I would've expected it to be at least the same. Also, there are many corners at the tracks that I run that a SM can go flat whereas I have to lift.
12-06-2017, 09:24 PM
#62
12-06-2017, 09:29 PM
#63
Still working on having enough b......ravery to take T8 @ Mosport flat......
Gary
12-06-2017, 09:32 PM
#64
Rennlist Member
Can someone explain in a little more detail Matt's data? What does the percentage refer to? Percent of throttle or percent of the lap on throttle or percent of the lap at WOT? HELP!
12-06-2017, 09:58 PM
#65
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One of the most basic and valid measures for determining something as simple as an objective evaluation of handling improvement is percentage wide open throttle (defined in this case 85% throttle position or higher) over the course of one lap’s distance.
One of the ways professional race engineers filter out a drivers subjective valuation of a handling change is to look at this number. Because the throttle position is the most direct and immediate window into a driver’s mind, of their confidence. If they like what they feel, they add more, or keep it down more often.
Most race engineers and top level racing drivers start with the idea of 100% WOT over the distance of the lap. Of course, this is not possible, but folks like Ross Brawn’s first question is “what is the one thing that is getting in your way of going faster?” Then they pick away at it.
The problem with this metric is that to get accurate readings and comparisons, the drivers measured need to be functioning at a VERY high level, capable of record or near record (at competitive series at the highest level) lap times, varying no more than hundredths to a maximum of a few tenths over the course of several laps.
Normally, the difference engineers are looking for in this number (% WOT over a lap distance) is in tenths or hundredths, also.F1 uses this measure all the time, and each track has a different target percentage.
I would want to sample only the best, National Champion or winning Conti ST, GS, GTD and GTLM drivers to make a comparison between small, medium and big bore car WOT percentage, but my observations parallel Matt’s. There are a lot more similarities than differences in this measure between small, medium or big bore cars, when driven close to or at their potential.
One of the ways professional race engineers filter out a drivers subjective valuation of a handling change is to look at this number. Because the throttle position is the most direct and immediate window into a driver’s mind, of their confidence. If they like what they feel, they add more, or keep it down more often.
Most race engineers and top level racing drivers start with the idea of 100% WOT over the distance of the lap. Of course, this is not possible, but folks like Ross Brawn’s first question is “what is the one thing that is getting in your way of going faster?” Then they pick away at it.
The problem with this metric is that to get accurate readings and comparisons, the drivers measured need to be functioning at a VERY high level, capable of record or near record (at competitive series at the highest level) lap times, varying no more than hundredths to a maximum of a few tenths over the course of several laps.
Normally, the difference engineers are looking for in this number (% WOT over a lap distance) is in tenths or hundredths, also.F1 uses this measure all the time, and each track has a different target percentage.
I would want to sample only the best, National Champion or winning Conti ST, GS, GTD and GTLM drivers to make a comparison between small, medium and big bore car WOT percentage, but my observations parallel Matt’s. There are a lot more similarities than differences in this measure between small, medium or big bore cars, when driven close to or at their potential.
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12-06-2017, 10:20 PM
#66
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Originally Posted by wanna911
even maintenance throttle too early will cause less front grip, especially in a 911. Some front engine cars can get away with very little pause, but if you are using all of the grip for turning, there is a moment where there is none left for throttle. As worded to me by Andrew Davis
12-06-2017, 10:37 PM
#67
The pause on either one of my M3s is very very short, but it is there. One of the cars is very much a street car, the other much more racy - likely has to do with weight distribution which is pretty much the same for both cars.
-Mike
-Mike
12-07-2017, 01:06 AM
#68
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Peter's post is basically correct, but I didn't post time at WOT, I posted average throttle position not including zero. I could do percentage of time at wide open as he said, but can't do it for a few days. Maybe Peter can get some good comparisons from his data?
12-07-2017, 06:27 AM
#69
Originally Posted by Matt Romanowski
Peter's post is basically correct, but I didn't post time at WOT, I posted average throttle position not including zero. I could do percentage of time at wide open as he said, but can't do it for a few days. Maybe Peter can get some good comparisons from his data?
12-07-2017, 08:18 AM
#70
Rennlist Member
I wouldn't expect the numbers to be a ton different but, ignoring aero cars, I'd expect an inverse relationship between the percentage and HP.
12-07-2017, 11:08 AM
#71
Nordschleife Master
That's even better (in bold).
Ed, that's difficult to answer as one size does not fit all, but the best drivers I've worked with CAN'T go to throttle (as the yaw rate of change is going on) and they often DO go to modulated throttle AS THE CAR REACHES the proper heading to PRESERVE the most desirable slip angle (or yaw), THEN go on to progress to WOT.
The point at which they do this depends on the length of radius and travel, topography and consistency of radius around the corner. If you look at the GT cars in the top levels, the period of the greatest yaw is somewhere AFTER turn-in (due to brakes trailed in) and closer to the approach (last few car lengths before) or at the apex (the slower the corner, the later the yaw moment).
I do NOT subscribe to the idea that IF a driver is able to go back to SOME power before the apex, that there is untapped gSum potential, as some confident drivers in a well-balanced car DO go back to power to SUSTAIN the proper slip angle and achieve an earlier "exit heading lock." But the yaw rate-of-change HAS to come first. And that is often accompanied with a "no pedal" condition.
For sure, IF THE NOSE COMES UP before the yaw rate of change occurs (which would come from releasing brakes TOO soon, or by going back to power BEFORE the car points into the corner), THAT would be a problem.
Here's one of my favorite videos. Matt is on the throttle ever so slightly to stabilize the car through T9 and T10, but good patience and clockwork precision at the slowest corners like T11. A handful, for sure.
https://youtu.be/HkvaXMKgbHY
Ed, that's difficult to answer as one size does not fit all, but the best drivers I've worked with CAN'T go to throttle (as the yaw rate of change is going on) and they often DO go to modulated throttle AS THE CAR REACHES the proper heading to PRESERVE the most desirable slip angle (or yaw), THEN go on to progress to WOT.
The point at which they do this depends on the length of radius and travel, topography and consistency of radius around the corner. If you look at the GT cars in the top levels, the period of the greatest yaw is somewhere AFTER turn-in (due to brakes trailed in) and closer to the approach (last few car lengths before) or at the apex (the slower the corner, the later the yaw moment).
I do NOT subscribe to the idea that IF a driver is able to go back to SOME power before the apex, that there is untapped gSum potential, as some confident drivers in a well-balanced car DO go back to power to SUSTAIN the proper slip angle and achieve an earlier "exit heading lock." But the yaw rate-of-change HAS to come first. And that is often accompanied with a "no pedal" condition.
For sure, IF THE NOSE COMES UP before the yaw rate of change occurs (which would come from releasing brakes TOO soon, or by going back to power BEFORE the car points into the corner), THAT would be a problem.
Here's one of my favorite videos. Matt is on the throttle ever so slightly to stabilize the car through T9 and T10, but good patience and clockwork precision at the slowest corners like T11. A handful, for sure.
https://youtu.be/HkvaXMKgbHY
Peter: I completed Ross Bentley's level II coaching certification class. Is "coasting " also another term for letting the throttle breath?
12-07-2017, 01:59 PM
#72
Rennlist Member
I think comparing % of WOT across cars with different HP is meaningless. Lets say I slap on 365 wide tires onto a 944. Now I can do the whole lap at 100% WOT. So now you would conclude that low HP cars can go 100% WOT. It's all about what tires and suspension the particular car has. It has nothing to do with HP to WOT percentage. The numbers that Matt listed are probably a result that lower HP cars usually have skinnier tires to make them more fun to drive and not be over-tired. Cars with more HP have fatter tires to allow them more grip on corner exit. Therefore they might have more ability to go WOT at a higher percentage through a corner.
12-07-2017, 02:31 PM
#73
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I think comparing % of WOT across cars with different HP is meaningless. Lets say I slap on 365 wide tires onto a 944. Now I can do the whole lap at 100% WOT. So now you would conclude that low HP cars can go 100% WOT. It's all about what tires and suspension the particular car has. It has nothing to do with HP to WOT percentage. The numbers that Matt listed are probably a result that lower HP cars usually have skinnier tires to make them more fun to drive and not be over-tired. Cars with more HP have fatter tires to allow them more grip on corner exit. Therefore they might have more ability to go WOT at a higher percentage through a corner.
12-07-2017, 03:49 PM
#74
Originally Posted by StoogeMoe
I think comparing % of WOT across cars with different HP is meaningless. Lets say I slap on 365 wide tires onto a 944. Now I can do the whole lap at 100% WOT. So now you would conclude that low HP cars can go 100% WOT. It's all about what tires and suspension the particular car has. It has nothing to do with HP to WOT percentage. The numbers that Matt listed are probably a result that lower HP cars usually have skinnier tires to make them more fun to drive and not be over-tired. Cars with more HP have fatter tires to allow them more grip on corner exit. Therefore they might have more ability to go WOT at a higher percentage through a corner.
12-07-2017, 03:57 PM
#75
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You will not go 100% wot in a 944 doesn't matter how big the tires are. Maybe a indoor level kart on a full size track can go 100% non brake throttle but a full size car maximizing corner speed will need time off throttle and brake. You simply can't WOT or even apply throttle 100% of every not braking moment of every turn period. It' about weight transfer and handling dynamics.