Lotus Elan Central

Goodwood Spin

Too close for comfort this time. Tell me where I went wrong I'd be interested to know.

C

Wow, glad you didn't break anything! (including you ^^)
Well I am not an expert but I would say you turned too early to the apex, and the track seems bumpy there. Maybe too much throttle, too (as you said in the description).
Anyway, I would be interested in a good explanation too

(PS: a guy made something similar with his Esprit V8 (at 3:30): https://www.youtube.com/watch?v=F7GTuKde0-o — it's amazing to me that he then continues to drive fast)

Glad I didn't (couldn't) take up your offer Chris

Glad you're OK - what numbers have you picked?

Will call you when I feel a bit better

Glad it worked out for you. Too much power too soon.

Steve

chris.t wrote:Goodwood Spin

Too close for comfort this time. Tell me where I went wrong I'd be interested to know.

C

I think you were still hanging on to the inside line with some left lock applied when you put the power down and the rear end came unstuck.
Also appears the track falls away into a hollow just after the crest so the car is going to get light and more likely to come unstuck.
Maybe better to let the car run to the middle of the track and gently left again a bit later to deal with the gentle left curve following..

I don't think St Mary's actually has an ideal 'clipping point' apex as it comes after a shallow right hander and speed determines to what extent the car can be moved across to the extreme right for the ideal entry
- been watching some racing on Youtube and many different ways to take it depending on characteristics of car and where competitors are...

Where you really went wrong was the choice of car ... wouldn't have happened in an M100..

lotusflasherman wrote:Where you really went wrong was the choice of car ... wouldn't have happened in an M100..

We can't go that fast.

How early in the session was this Chris? I don't know the circuit but it looks like the first proper left hander. So all the forces concentrate on the offside tyres which may still have been a bit cold? Also you were obviously applying throttle - though didn't seem extreme to me - did you boot it or bringing it in smoothly?

Amazed how fast it let go and so pleased you missed all the hard stuff. Better luck next time.

Thanks for all your replies. Things you should also know. I had stiffened the suspension before this session. The spin came after about 7 laps of hard driving. I have compared line and engine note and all laps are very similar although I think I was getting faster with every lap. The rear tyres are now shot, left more so than right.

Someone has suggested that this wouldn't have happened with a load.

Glad your OK, was that the VX? , how is it running overall apart from that spin ?

chris.t wrote:I had stiffened the suspension before this session.

I think it could be at least partly because of that, as I said the track seems bumpy as far as I can tell from your video, so a stiffer suspension is not necessarily a good idea in my own non expert opinion.

chris.t wrote:Someone has suggested that this wouldn't have happened with a load.

You mean into the boot? Not too sure about that. Maybe a little since it would have had added some rotational inertia and added some traction on the rear end but on the other hand the whole point of a mid engine car is to reduce the rotational inertia so that it spins faster when you want to turn ... or correct an oversteer.

Not load, LSD sorry my useless predictive text and poor eyesight!!

Scott J wrote:Glad your OK, was that the VX? , how is it running overall apart from that spin ?

Yes Scott it's running well. It really is a dedicated track car which it does very well. Taking it up to the lake district camping, definitely not, there's only one car for that!

Thanks for showing us your new car Geoff

chris.t wrote:Thanks for showing us your new car Geoff

+ 1

chris.t wrote:Thanks for all your replies. Things you should also know. I had stiffened the suspension before this session. The spin came after about 7 laps of hard driving. I have compared line and engine note and all laps are very similar although I think I was getting faster with every lap. The rear tyres are now shot, left more so than right.

Someone has suggested that this wouldn't have happened with a load.

Not surprised about the tyres, that's the only left hand bend on the circuit, apart from the 2nd bits of chicanes which are a bit mickey-mouse. It's nearly all right turns so working the left tyres most of the time.

What suspension stiffness had you put on? Hope you hadn't wound them up to max' like a lot of people think they should do.

I raced Mini Miglia in the 70's and at a Snetterton test day there was a guy with a BDA engined Escort using the adjacent pit who came in and said 'It's great for the first few laps but then becomes 'king un-driveable'. I heard a creaking noise and happened to notice his Escort slowly coming up to it's normal ride height as it sat in the pit lane and pointed it out. He had his shockers rebound so stiff that after a few laps they were fully compressed and he had no suspension movement left. Backing them off a bit sorted it out.

First Mini we built had Konis and their Setup Instructions were to start on softest settings for Bump & Rebound and move upwards from there... bit of theory on setup here that may be useful - www.koniracing.com/rrtuningguide.cfm

Problem with Konis was we had to take them off to adjust by turning the piston rod but found they were already a bit firm for the rear of a lightened Mini. The guy who drove that car rarely changed the settings as it was such a p.i.t.a.
When we built my 'super lightweight' Mini I went to Spax, in Kentish Town near me, and got them to build me a set that started soft so I could use the range offered by the adjuster screw. Rears I kept quite soft but increased the front as most of the weight was the power unit up front, but would change the rears for the bumpiness of the track, or back them all off if it rained. Seemed to hang on well going flat out through what was the Snetterton Esses, now called Nelson, and we weren't allowed LSD's so setup was critical ...



My team mate tried a season in Special Saloons where LSD's were allowed and he didn't like the handling when a wheel lifted and the LSD kicked in - found it very unpredictable where it was going to go as understeer came and went and the back end would sometimes unstick.

I had the Nitron single way coil overs set to 10f/12r clicks out of 24, 24 being fully soft. After the spin I reset to 14/16.

Interesting re LSd but the vx is rwd and may well react differently.

chris.t wrote:I had the Nitron single way coil overs set to 10f/12r clicks out of 24, 24 being fully soft. After the spin I reset to 14/16.

Interesting re LSd but the vx is rwd and may well react differently.

Not 'silly hard' then... so should have kept moving OK. Found this for adjusting Nitrons on Elise/Exige ... presume VX will be very similar www.sector111.com/images/products/performance/suspension/nitron/Nitron_Tuning_Guide1.pdf
Interesting they say adjust Nitrons down from Full Stiff and Koni say go up from Full Soft...

Mini was fitted with a secondhand Salisbury LSD, clutch type, and user adjustable, and we were never certain how the previous guy had set it up but he'd been quite successful so fitted it as it came... Guys with loads of money were using Quaife LSD's. I think LSD's have progressed a lot since then. Certainly my Subaru spreads 250 bhp around 4 wheels so well it's a bit boring to drive - until it snows..

For the VX, my 'logic' tells me you were taking a left hand bend so right rear was more heavily loaded (by weight) than left rear but it was the right rear that let go ... I'm still trying to think how an LSD would have made any difference as I don't think the left rear was unweighted enough to start to rotate at a different speed for the LSD to have anything to correct, but I'd be interested to hear other peoples thoughts...

(lotusflasherman > At first sight your photo of the racing Mini is rather funny to the LHD driver in me since the RH side is invisible and the LH side is clearly empty )

Hi Phil, thanks for your analysis. I agree the right rear was fully loaded, I had slightly stiffened the damper settings, which coupled with the reverse camber of the track allowed the left rearto go light and to lose grip. This would imo give much more grip to the right rear which would want to push the car left. With the steering already to the left the result was as per the video. I think this is what prompted the question whether LSD would have been an advantage.

Cheers Chris