Copse Corner

[Mr.Jingles]

OK, I'm confused (doesn't take much).

I've been watching vids of FF1600's at Silverstone as I get myself all worked up for this years WHT (never driven the National circuit before, only Southern and Stowe). Most of it is straight forward and as I expected but Copse has got me thrown. Some drivers are dropping to 3rd before taking it, powering around and changing within a second or two of clearing it - others hang on in 4th.

Watching the vids it seems that the 2nd approach is slower because the engine gets out of peak power, but it's the faster drivers doing it so clearly that isn't the whole story. What am I missing? Are the 3rd gear guys running a higher 3rd?

I've only got Testing on Friday (best I could manage budget-wise) so I've got 2 sessions to sort this and the suspension

[terence]

Just a little 'something' is that every gear change cost's a little time.

[tristancliffe]

You might find that in the higher gear the car is more stable. Plus the lower revs means you try to carry more speed anyway, so you end up going a bit quicker. Plus you can concentrate 100% on nailing the corner, rather than worrying about a downshift and then an upshift.

Try both (if your gearing allows), but I would tend towards staying in 4th if there isn't much in it.

[JNWRF01]

remember there is a small rise on exit up to the hairpin - so in 4th you may labour dragging the car up the hill. For what its worth - I use 3rd in a Zetec (obv top in a F4 as you have wings/big tyres).. suspect in a Kent its almost flat - so prob 4th

[Steve Burns]

Personally I prefer the 4th gear option, but do remember to brake a little bit before turning in The really quick guys probably just get away with a lift. Although it will probably be wet this weekend so definately 3rd in the rain

Out of interest do you use 2nd or 3rd at the Castle Combe Esses as that is a similar dilema?

[Mr.Jingles]

I've always been told that changing down gears costs you nothing itself as you are in a braking zone anyway - unless you mismatch the shift and chirp the rear OR the engine braking drags a few extra mph off than you were planning?

Think I'm gonna stick to 4th unless it's wet - I'l trade away a bit of exit speed up the slight rise to give me a less 'exciting' entry!

Cheers guys.

Originally Posted by Steve Burns

Personally I prefer the 4th gear option, but do remember to brake a little bit before turning in The really quick guys probably just get away with a lift. Although it will probably be wet this weekend so definately 3rd in the rain

Out of interest do you use 2nd or 3rd at the Castle Combe Esses as that is a similar dilema?

Hi Steve!

Yeah, it is looking a bit wet on the BBC weather:

Fri - Light Rain
Sat - Light Rain
Sunday - Heavy Rain

TYPICAL.

Esses is tricky - if I'm 'busy'/it's wet 3rd is the way to go, otherwise I'll drop to 2nd. Tom sticks to 3rd.

Given my results to date, compared to Class Champ, this could be duff advice But I seem to be able to get away better this way and get a good run right down to Tower.

[graeme]

Originally Posted by Mr.Jingles

I've always been told that changing down gears costs you nothing

But then you've got to have a lift - and loose a tiny bit of momentum - as you shift back up to 4th after the corner. Its such a short dab on the brakes in most cars that I'm genuiely suprised that there's any consideration of 3rd (but I know nowt about single seaters). And many people just use the runoff anyway

If its wet, remember the wet Copse line - miss the apex by a foot or so to get out of the smooth, rubbery F1 groove. And all the way 'round the outside of Luffield.

[Alfie72]

I preface my comments by admitting I'm not a driver, however...

The way in which you take Copse is governed by the way you drive and consequently set your car up. This in turn has a bearing on which gear since your car's attittude may be flat or nose down dependant upon whether you left foot brake or not (message to the world, there are still people out there who don't/can't.)

So in some respects, it's up to you, since you may not have the "free" time to down shift. You may not need to either.

Plus, you should bear in mind that the exit up to Maggots is up-hill. If your rev range is such that you can remain in your engines power band throughout, then ok. But if not, again the decision is made for you.

[RF_Racer]

Copse is an interesting corner, along with Stowe. When I first drove at Silverstone I kept running wideover the kerbs on exit, as the turn in is blind.

During testing in my FR, I was trying to get the lines right and aiming to hit the inside kerb everytime, not easy, but doing so allows you to get on the power earlier. I played about with doing various things, initially I was just touching the brakes lightly (mentally your head is telling you to brake, because its such a fast entry and blind) then no brakes, just lifting changing to 5th, I also tried to carry in 6th with a lift, but acceleration was slow, so 5th was the best... Now I just need to get back out testing and try and go through it 10-15mph quicker. Will be fun trying.

People are saying they are doing Copse flat, well that would be impressive to see, with data to back it up, but in most cases people seem to be lifting and trying to get back on the power as early as possible.

[JohnMiller]

For FF1600 it should be top with only a little lift. Do a couple flat in qual and run over the tarmac run off "accidentally."

[RF_Racer]

Originally Posted by JohnMiller

For FF1600 it should be top with only a little lift. Do a couple flat in qual and run over the tarmac run off "accidentally."

What is their mid corner speed? Likewise for an F3?

[Chris Y]

Nice to see old threads getting brought back to life

[JamesH]

Originally Posted by Chris Y

Nice to see old threads getting brought back to life

AFAIK, Copse corner is still there....

[Alfie72]

Originally Posted by Chris Y

Nice to see old threads getting brought back to life

My wardrobe is full of old threads

[RF_Racer]

funny comments...

[Red Dog]

Originally Posted by RF_Racer

What is their mid corner speed? Likewise for an F3?

No one seems willing to say......
I drive a 750 Formula - it has almost no power at all so one is desperate to stay on the throttle at all times. I take Copse with no lift at all and it does not need the whole track. On a good lap speed is 102mph. Lateral G is 1.6

[RF_Racer]

Originally Posted by Red Dog

No one seems willing to say......
I drive a 750 Formula - it has almost no power at all so one is desperate to stay on the throttle at all times. I take Copse with no lift at all and it does not need the whole track. On a good lap speed is 102mph. Lateral G is 1.6

No one has said anything.. Im glad you did!

Next time around I am going to try to carry even more speed through it, just lift and try and get on the power earlier...hopefully get the car to my liking on setup, aim is for about 110, running at 40mm prob dont help either..

[tristancliffe]

Don't even think about the 40mm aspect - the car is more capable than you or I are, even at 40mm. If you can just manage 110mph then the car will be able to manage 115mph. We as the driver are the weak link in the equation. Worrying about setup and ride height is making you slower.

But in your car a lift will be slow. You will need to brake, possibly quite early and probably not very hard. Then you need to be back on full power LONG before the apex (a surprisingly early apex as well as it's a fast, opening corner).

Remember - corner speed, especially midcorner speed, is the least important part of racing cars. What you need is EXIT speed. Slow in, fast out. Sacrifice a smidgen on entry so that you can get the car turned and the power on hard earlier. Everything else - lifting, braking, turning points, apex points, how much kerb you use is secondary to getting corner exit speed.



If you do 110mph at the apex, and therefore do 113mph by the start of the exit kerb, you will be slower than if you do 105mph at the apex but 116 by the exit kerb.

You already know that my minimum speed is 107mph and peak lateral g is 1.86g.



Edit: Because I'm a talentless oaf, you can see my lift after the apex as I would have run out of road. That was at 108mph, and the tiny lift cost me nearly 2mph and a lot of time - I reckon I lost two tenths from that alone, maybe more.

[RF_Racer]

Its definately an interesting corner you can play with different techniques, I dont think braking is necessary (might be comfortable for you, as you can make it work) I think the problem is I was not getting on the power early enough so that made my mid corner speeds a bit lower than they should have been. I think its still do able with just a lift and be brave to get back on the power earlier

[tristancliffe]

It may well be. The Renault differential has 45% locking on coast and power, and a much higher preload torque, so you'll probably get more power understeer than our car. That would translate on the track (all other things being vaguely equal) to your car needing to be "turned and squirted" rather than using "conservation of momentum" - i.e. brake to the apex, turn the car, get on the power. Quite unconventional really. But it'll be why your car will be very competitive at Mallory, Brands (Indy) and Cadwell, as the bigger F3 cars will struggle in the corners.

The trouble is that it is impossible to get on the power earlier if your cornering at maximum potential - the traction ellipse. If you lift and turn so that you can't go into the corner any faster (without crashing) then you will have to wait to get on the power. If you brake and turn (not necessarily in that order ), and set the car up for a wee bit of understeer (although that may be to your detriment at every other corner - oh the joys of race car setup!), then you can get on the power earlier and earlier.

You are right to concentrate on the power application point. But I think you are wrong to think that slowing less will make you faster. And, of course, the faster one tries to go, the slower one actually goes - make the car do the work. Be smooth. Concentrate on hitting apexs and braking points etc, and the speed will come. If you TRY to go fast then you make 10 times as many mistakes (most of which are small, but nonetheless mistakes) and go slower. I think it's one reason people go quicker in a race (apart from having learnt the car and track in practice) - you watch the car ahead and try to race him, rather than thinking about HOW to drive the track.

[RF_Racer]

Yeah thats the other thing I need to get looked at, I am not sure what the preload is at the moment, but it would have lost a fair bit over the last year or so, but will get that back to its recommened setting.

Whats the locking percentage on a Dallara?

[tristancliffe]

It can be varied with different ramps in the differential, with 30°, 45°, 60° and 80° ramps, with a larger angle giving a smaller locking factor. What they equate to as a percentage I don't know. Our car has 60°/80° on coast/power, so relatively free, but it doesn't seem to allow inner wheel wheelspin or instability under braking, so we'll leave it alone. We set a 20lb.ft (27Nm) preload when we rebuilt the car, and it seems to have stayed pretty close to that since.

I am surprised at the level of locking in the Renault. Maybe less would be better for amateur drivers, so that the car will turn a bit more easily, even if ultimate traction is slightly reduced.

Edit: Oh, and the Dallara can have different number of friction plates in use by swapping the order around. We use the maximum number of plates, which gives the most locking factor. But we had to start somewhere, and I see no reason to change now!

[Chris Y]

Doesn't that make it very snappy on transition from power to coast, and vice-versa?

[tristancliffe]

Nope! 60/80 with 6 plates and 20lb.ft is the Dallara recommended initial setup, and the car spends most of its time on rails.

[ianpearson]

Originally Posted by RF_Racer

Its definately an interesting corner you can play with different techniques, I dont think braking is necessary (might be comfortable for you, as you can make it work) I think the problem is I was not getting on the power early enough so that made my mid corner speeds a bit lower than they should have been. I think its still do able with just a lift and be brave to get back on the power earlier

I'll try to look at my old data over christmas but i reckon it was about 110 mph apex speed in the FR2000. You are right about no braking, its what i was told & did, just lift & knock it down to 5th (it fealt dreadfull) then back on the throttle ASAP preferably pre apex. I heard claims of flat through there but never witnissed it.

How's your testing going?