Respectable trackday lap time for Silverstone GP Arena.

[wellground]

RacerMike said:

Funny you should mention that. Jonny's a good friend of mine and my 2:33 in the Focus was about 30mins before the 2.19 in the Cayman. 1 up with some Tyre pressure tweeks, the GT4 would easily do a 2.18 or better. Usually, an amateur should be coachable to within 5s of a pro, so 2.24 should be easy.

The 2.19 lap is here for anyone interest: Cayman GT4 2.19. Liberal use of run off kerb, as per GT 'regulations'

Amazing video, fantastic driving. Great to watch.

[Olivera]

Superb lap in the Cayman GT4, even makes the 2.17 stated earlier in the thread from a 675LT seem piss poor.

I wonder how much faster the GT4 would be with less intergalactic gearing?

[NJH]

Just shows how big the gap is between driving quickly and actually fully exploiting the available limits of the tyres. Through a combination of my own and a friends data logging and rFactor simulation I worked out that an extra 2 mph in corner speed will yield about 3 seconds or more over the lap there (3.7s in the actual cases I was looking at for the 944 or 968). That level of commitment on the above video is easily going to keep a couple of mph more mph on the boil through those corners. Shame I never managed to put that into practice myself when I was racing but hey ho.

[LaSource]

Ok, I'll put this out there for a bit of fun ...be nice to me!

After Jonny's lap in the GT4 I did a side by side of his with one of my laps from March last year just to see visually where I was wrt to comparison with an expert. Seems to be about a 5 sec gap over the lap...

His braking is so deliciously late and 'aggressive' and I guess it accounts for so much of the time...plus the faster corner speed of course. Hence a vbox trace would be academically very interesting.

I reckon I'm now over a second quicker than back then...but then he also had a full size passenger! ...and his vid may be slower by another second or so due to conversion!

(I'm ignoring all the other factors like conditions on the day, tyres, etc, etc - so the comparison is really just for fun)

https://www.youtube.com/watch?v=hs5eeKqk0pc

Edited by LaSource on Monday 20th March 22:16

[Cunno]

Thanks LaSource

Enjoyed that I was doing the same studying the 2:19 vid his late breaking something else real eye opener and how carried the trial to the apex skills I don't have.

[HokumPokum]

my word. that's some committed cornering.

[LaSource]

Cunno said:

Thanks LaSource

Enjoyed that I was doing the same studying the 2:19 vid his late breaking something else real eye opener and how carried the trial to the apex skills I don't have.

Well, that's why no one pays us to go racing

[RacerMike]

Cunno said:

Thanks LaSource

Enjoyed that I was doing the same studying the 2:19 vid his late breaking something else real eye opener and how carried the trial to the apex skills I don't have.

Braking phase is by far and away the biggest area of time loss for most, and it's one of the main areas I end up working on with people. Braking to the apex in particular helps in anything with a rear weight bias (i.e. 911s, Caymans and, would you believe it, Caterhams!) and nailing the braking point/maximising brake force/reducing the length of the braking area finds huge chunks of time.

If it helps, here's a VBox video from GT4 Qually at Silverstone 2 years ago. Afraid we weren't running brake pressures, but you get a decent idea from the Accelerometer gauge. It wasn't the tidiest of laps, but the Cayman really isn't that far off anyway.....this was a 2:15.3

Edited by RacerMike on Tuesday 21st March 23:00

[v8bloke]

Looking at the last clip, https://www.youtube.com/watch?v=qZFUozd4kCg who else double apexes luffield. Its hard to get just right but when you do it seems so much quicker.

[Elderly]

v8bloke said:

who else double apexes luffield. Its hard to get just right but when you do it seems so much quicker.

Always (in the dry) - and I don't think it's hard to get right.

I find the 'new' (faster than Copse!) right hander at Abbey hard to get right.

[RacerMike]

v8bloke said:

Looking at the last clip, https://www.youtube.com/watch?v=qZFUozd4kCg who else double apexes luffield. Its hard to get just right but when you do it seems so much quicker.

I find it depends a lot on car and setup. That weekend, the car had just been rebuilt with new dampers, and we were a bit 'thumb in the air', so it was quicker to do the double apex. With more downforce or a stiffer car, it can however be quicker to hug the apex the whole way round, but it depends a lot on steady state balance.

[loggyboy]

Elderly said:

I find the 'new' (faster than Copse!) right hander at Abbey hard to get right.

I found it very deceptive, I started the day assuming it would need a fair amount of braking, but was surprised how easy it was to make up massive amounts of time there, eventually reducing a dab on the brakes to a lift off only. Obviously in the Clio I wasnt carrying a huge amount of speed in to it but never the less it felt quick!

[mpit]

I think Abbey and Copse have to be the two most commonly over-braked corners.

From an amateur perspective; I haven't played with technique with a real car too much at Silverstone, but having recently got into racing sims I've found that braking at the same spot and getting off the brakes a little earlier allows a much higher entry speed, presumably because it allows the car to be more settled before turn-in. Where I think the natural instinct is to perhaps brake later to find speed through the corner, which just doesn't work.

I hope to put this into practice on Tuesday next week

[billyboysm3]

Really looking forward to taking my E46 M3 here. Only ever driven it 3 times and its always been raining, Abbey and Copse in the wet have to be my favourite corners, should be
epic in the dry.

Keep posting the videos

[isaldiri]

mpit said:

I think Abbey and Copse have to be the two most commonly over-braked corners.

From an amateur perspective; I haven't played with technique with a real car too much at Silverstone, but having recently got into racing sims I've found that braking at the same spot and getting off the brakes a little earlier allows a much higher entry speed, presumably because it allows the car to be more settled before turn-in. Where I think the natural instinct is to perhaps brake later to find speed through the corner, which just doesn't work.

I'd agree with that in the real world. For any fast corner (and copse/abbey are 80-90+mph on road tyres) getting the car settled makes a big difference.

[loggyboy]

mpit said:

but having recently got into racing sims I've found that braking at the same spot and getting off the brakes a little earlier allows a much higher entry speed, presumably because it allows the car to be more settled before turn-in. Where I think the natural instinct is to perhaps brake later to find speed through the corner, which just doesn't work.

Both need a dip of brakes (or lift off) to get the front to grip IME. Very much a car to car based view tho, would be flat out with no need for it in something with 100hp!

[NJH]

isaldiri said:

I'd agree with that in the real world. For any fast corner (and copse/abbey are 80-90+mph on road tyres) getting the car settled makes a big difference.

Definitely. That Abbey section is one of the few areas at Silverstone I have well nailed, the key is not to go to crazy with carrying so much speed in that you end up compromising the following left hander. For this reason I keep it a tiny bit under the limit on the right hander so I can be hard on the throttle all the way through the following left. It is blooming exciting like that and was giving me 103 to 105 apex at 1.3g in the 944 on road legal tyres (DZ03g). Its the low speed stuff at Silverstone I can't stand, never been happy enough and tidy enough with them, they also always give the feeling that the car is crawling along and loosing a ton of time.

Also keep an eye out for slight unsettling bumps on that right hander. Unless they have resurfaced it there was a slight bump on the way in if you tried to take it too tight that kicked the car out.

[mpit]

I was at Silverstone yesterday in an Audi engined Elise.

I was quite unlucky and didn't get a single remotely clear lap, which wasn't helped by the car breaking after lunch. The best lap I have timed is 2:33 with a best rolling lap of 2:30 and a theoretical best of 2:25.

If I got anywhere near 2:25, I'd be chuffed on road legal rubber!

Anyone got a reference time with a decent driver in an Exige or similar?

[Ruxpin]

mpit said:

I was at Silverstone yesterday in an Audi engined Elise.

I was quite unlucky and didn't get a single remotely clear lap, which wasn't helped by the car breaking after lunch. The best lap I have timed is 2:33 with a best rolling lap of 2:30 and a theoretical best of 2:25.

If I got anywhere near 2:25, I'd be chuffed on road legal rubber!

Anyone got a reference time with a decent driver in an Exige or similar?

On Monday my standard 118bhp S1 elise on yokohama AD08R road tyres was doing 2:42/2:41 according to the gopro.

Fantastic day once the fog lifted, really didn't matter it was sessions as most were flying around and driving standards were generally very good as usual with LOT.

[eracing2011]

mpit said:

I was at Silverstone yesterday in an Audi engined Elise.

I was quite unlucky and didn't get a single remotely clear lap, which wasn't helped by the car breaking after lunch. The best lap I have timed is 2:33 with a best rolling lap of 2:30 and a theoretical best of 2:25.

If I got anywhere near 2:25, I'd be chuffed on road legal rubber!

Anyone got a reference time with a decent driver in an Exige or similar?

Elise 111R all stock; ~2.35

https://youtu.be/Pulfg-g5AEA

I don't think there is much more time to be gained...