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Trackphoto's jumped in my car and did a few laps at general practice on 20/08/16. It took me a few more sessions to get under his time.

The Vbox keeps the fastest lap in memory to use for predictive timing. Hence when coming out of T2 the predictive timer kept saying that I was loosing time I was puzzled as to why... In the end I set a new predictive baseline time, but it made me curious.

Pulled my previous PB (1:27) and compared it to Trackphotos for T2.

Truth hurts... Trackphotos did a light tap on the brake and let the corner wash speed off, something I don't do. Me, I braked 28m earlier BUT Trackphotos was 15km faster by the time he braked.
The brake distance was about the same 50m, I washed off 23kmh whereas 36 for trackphotos.
Turn in was about the same place, BUT somebody was 13kmh faster
I was on the gas about 30m earlier... BUT, Trackphoto was at full throttle in 36m after finishing braking whereas I used 124m. Lesson just in this! Hence why somebody got 191kmh and me 188.

Many thanks to Trackphotos, guaranteed he will get the keys again to do some more laps.

T2 by Eipeip, on Flickr

It was lots of fun, thanks for the drive. I reckon there's still time to be gained exiting t2, I didn't get it right on any of my laps. I'd say probably 195kmh vmax on the back straight with a perfect run through t2. Would be using all the ripple strip to do it though.

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Slow in fast out is a lie designed to protect instructors.

The fastest way is fast in fast out.
Obviously.

But my instructor's definition of slow is probably still faster than your definition of fast

Slow in fast out is a generalization intended to highlight the importance of not going too fast into a corner as it ruins lap speed more than slowing too much on way in but getting good drive out..

So he broke a bit later and harder, had more weight over the front wheels so it turned in better, got a good line to accelerate out of the corner, you broke earlier so had less weight over the front tyres, more understeer, because you were slower you got on the gas earlier but you were still cornering so you had to feather the throttle to maintain acceleration?

NitroDann wrote:Slow in fast out is a lie designed to protect instructors.

The fastest way is fast in fast out.
Obviously.

yes, well sorta...but...in high powered cars exit line can be more important than corner speed. Not an issue for most mx5s though, and corner speed is king!

Ned Loh wrote:yes, well sorta...but...in high powered cars exit line can be more important than corner speed. Not an issue for most mx5s though, and corner speed is king!

Actually low powered cars need to maximise their exit more than hipo cars as they dont have the luxury of using the horsepower to make up for a bad exit..

rascal wrote:

Ned Loh wrote:yes, well sorta...but...in high powered cars exit line can be more important than corner speed. Not an issue for most mx5s though, and corner speed is king!

Actually low powered cars need to maximise their exit more than hipo cars as they dont have the luxury of using the horsepower to make up for a bad exit..

both high and low powered cars need to 'maximise' their exit for best lap time, however 'maximise' may mean different approaches in different cars.

What I was trying to say is that in order to get the best lap time a high powered car the driver may compromise their max corner speed for a better exit line in cases when it will allow them to be on the gas earlier and more than a 'max corner speed' line would.

99% of mx5s, being relatively low powered, need to use the max corner speed line for best lap times

Okibi wrote:So he broke a bit later and harder, had more weight over the front wheels so it turned in better, got a good line to accelerate out of the corner, you broke earlier so had less weight over the front tyres, more understeer, because you were slower you got on the gas earlier but you were still cornering so you had to feather the throttle to maintain acceleration?

In a nutshell, YES.

This is the lap. The numbers in the red box LR/RR are the suspension sensors in the rear. At rest the LR = 70 and the RR = 73. So down the back straight when it is 62/63 means that there is 64/80kg (144kg) additional weight on the rear wheels (acceleration/downforce). Going into T6 the LR/RR go up to 92 this implies 312kg less weight on the rears.

I may get bored on the weekend and do the maths on the weight transfer differences.

Ned Loh wrote:

rascal wrote:

Ned Loh wrote:yes, well sorta...but...in high powered cars exit line can be more important than corner speed. Not an issue for most mx5s though, and corner speed is king!

Actually low powered cars need to maximise their exit more than hipo cars as they dont have the luxury of using the horsepower to make up for a bad exit..

both high and low powered cars need to 'maximise' their exit for best lap time, however 'maximise' may mean different approaches in different cars.

What I was trying to say is that in order to get the best lap time a high powered car the driver may compromise their max corner speed for a better exit line in cases when it will allow them to be on the gas earlier and more than a 'max corner speed' line would.

99% of mx5s, being relatively low powered, need to use the max corner speed line for best lap times

I agree.

Speed isn't everything and in every car you need to take the maximum speed which keeps you on the optimum line.

The challenge is that the optimum line changes based on multiple factors including speed, Aero, grip and power.

Experimentation with different approaches and data logging is a good way to determine the faster line.

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The 'ol having the testicular/breastacular fortitude to extend the time on the throttle and brake harder and later ... without braking too late.

Okibi wrote:The 'ol having the testicular/breastacular fortitude to extend the time on the throttle and brake harder and later ... without braking too late.

You definitely know when you get it wrong. If you're not getting "a moment" then you know you are well under the limit. My trick is to not focus on the corner itself and instead my brake point. Then I follow this simple flow chart. (Note: Best applied on a race track)

[1] Did I hit the apex and make it around the corner ----> YES ---> [2] Brake Later ---> go back to [1]
|
[3] NO ---> Change undies and brake a bit earlier and go back to [1]

I've never had a problem reaching the limit. It then relies on a little bit of skill to make sure you don't damage stuff when you do but that only comes with practice

I had that moment in marks car during that session locked brakes into t2, lol. Should never happen, t2 is so fast that it only takes a light tap. Forgot the ad08rs aren't quite as grippy as my nittos, and locked up when I was trying to load the front left up. To be fair, I only did 2 flying laps so I reckon with a tad more practice in marks car, id be braking lighter and more briefly, just enough to load the corner instead of take speed off.

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You're just too fast dude. Slow down.

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