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I went to Donington on Sunday. I had a mixed day, but I'm please I went.

The front brakes still don't work properly, so I was having to leave loads of braking room.
The rear of the car was very loose, but it got better during the day with suspension changes.

I got black flagged for noise (103.2dB), broke 3 of yoofs small drill bits trying to drill holes to lock wire the extra silencer on, got a puncture (no spare wheel, so had to take the spare tyre to the nearest KwikFit), spun on the sighting laps (although that was because I wanted to find out how bad the brakes were - turns out very bad), spun trying to move over to let someone past (due to the tyre already deflating) and spun again when I tried to push the brakes too hard, and ended in the gravel trap.

However, I figured out how to adjust the damping on the suspension, so went full hard on the front, and full soft on the rear which helped, and then disconnected the rear ARB when changing the wheel with the puncture. Each change made the car better.

I'll now pull the calipers off and get them refurbed, and also get a big centre silencer fitted.
I also need some new tyres, as these are all starting to resemble 50p pieces after all the spinning.

Some pictures:

Wow sounds like quite a day of swapping. Looks cool though!

It was. Not quick, but good fun though.

This arrived today:


Which contained these:


These will be going on instead of the Seat Leaon APs. Bigger and better, and known to be working.

I'll get them on the car this week, and see if that fixes the brake problems.

Did the strongbow come with them?

No, thank goodness, I can't stand cider!

I thought that was to help with the driving on the next trackday?

PhillipM wrote:I thought that was to help with the driving on the next trackday?

Based on the last outing, that would end in tears...

I fitted these just before Christmas, but was still unable to get a pedal. This could only mean the master cylinder had failed.
I ordered a new one, and it lay there for 4 weeks.
I gave up trying to make time and took it down to Stealth Racing, along with the brake bias valve. They fitted that, then found the brake servo had been changed at some point in the car's past, so the MC didn't fit. They tracked down the correct one, so I now have working brakes. Yay.

Next up, the car is going to have the alignment and corner weighting done, and then I need to fit a new silencer as the car was 108dB on drive by at Donington. I'm going to try to fit in a test day in the next couple of weeks.

I wasn't happy with how the car had handled on any of the outings so far, it just felt horrible. Turning in was an exercise in "guess how much oversteer will happen this time", I just couldn't get any confidence in the car.

I decided to take it to a local company called Spires Tuning, which is run by ex-JLR suspension designers, so they know a thing or two.
I arranged to drop the car of with Matt yesterday after work. He put it on the ramp, and looked at a few things, and made some comments.
Matt: "Front rebound is way too high, that will be source of the understeer".
Me "Er, it oversteers. A LOT"
Matt: "That's not possible, it should be understeering massively."
Me: "It feels like it's on ice. I'm sure the springs are too hard."
Matt: "What are they"
Me: "Can't remember, what KW specced. Hard though, around 800lb front, and something less on the rear"
Matt: "That sounds too hard, let's check"

So we checked the springs.
The fronts are 140/140 (so 140Nmm (800lbs)/140mm long).
The rears are 80/180 (so 80Nmm (500lbs)/180mm long).

Or not. I have the values the wrong way around. The rears are actually 80mm long, and 180Nmm, so over 1000lb rear springs!! What on earth KW used to calculate that I have no idea. I can only assume they missed the bit about removing the Haldex, but even then they are too hard.
That would explain why the rear of the car just skated everywhere.

Matt's working out all the ratios and weights, and I'll get some new springs. He'll then also set the camber, caster and toe (front and rear) to something where the car should be neutral.
No rear ARB for now either.

He will also be sorting out a new rear silencer, and is confident we can get under any track day limit with just a bigger silencer.

He's hoping to get it back to me by the end of the week, but it depends on lead times for springs and the back box.

I hope you'll be sending K&W some communication, be interesting to hear their explanation.

A tool for measuring spring rates is always something I've planned on making. It's one of those things that is massively useful on very rare occasions. When we've been really stuck I've calculated spring rates mathematically before, but it's a little hit and miss due to the nature of the measurements needed.

Glad you're heading in the right direction now (did you see what I did there).