Liam's Z4C race car project

Leesfarm07 · Post by **Leesfarm07** » Wed Jul 10, 2019 6:18 pm

Like the Acid Green caliper paint where did you get that from?

Liam22 · Post by **Liam22** » Wed Jul 10, 2019 7:27 pm

Leesfarm07 wrote: ↑Wed Jul 10, 2019 6:18 pm Like the Acid Green caliper paint where did you get that from?

https://www.ebay.co.uk/itm/111393483537

Leesfarm07 · Post by **Leesfarm07** » Wed Jul 10, 2019 8:34 pm

thank you

adam1985 · Post by **adam1985** » Thu Jul 11, 2019 1:42 pm

Liam22 wrote: ↑Tue Jul 09, 2019 10:10 pm 20190616_155101.jpg
20190616_161749.jpg

Looks like at least the thermostat, if not the pump as well, were not original as the OEM thermostat is metal rather than plastic, it was on mine at least.

Liam22 · Post by **Liam22** » Sat Jul 13, 2019 11:10 pm

Didn't quite sail through the MoT. Was feeling very confident but can you believe I had never tried the horn?! One of them had plain failed and the other had a broken wire. Made one good horn out of the pair and passed the retest the next day.

With that annoying formality out of the way, on with the fun stuff!

Crammed the boot full of tools and spares and headed off to Snetterton for a shakedown track day

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Spent most of the morning trying to get a decent ABS/DSC combo working. Even with the DSC turned off (long press on DTC button) it's still actually on. It'll let you have a small slide but still intervenes, and makes the steering feel terrible. So I went through the process of individually removing every single fuse related to ABS, DSC, and DTC. My goal was to retain the ABS while completely disabling DSC. No luck. So I ended up keeping fuse 43 removed which disabled ABS and DSC as this also had the best steering feel.

No ABS or DSC is a good way to get to know the car, but I had to brake earlier. Yes, ABS is better than me. Will something like Carly allow me to code the ABS/DSC system to my liking?

Had no problems with temperatures. The coolant occasionally spiked just over 110ºC and peak oil temperature was 122ºC which is no problem for the Millers Nanotech CFS.

Let the car cool down over lunch and then did a full spanner check on the brakes and suspension. I was pleased to find that nothing had fallen off, and only a few bolts needed tightening. Was surprised that despite meticulous torquing of everything, the main subframe bolts all needed a good amount of tightening.

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The afternoon was all about suspension setup. Noticed that the front left inside shoulder was significantly hotter than the outside (unusual!) which was because the adjustable top mount had slipped across to -4.0º camber. Moved it back to -2.0º which seems perfect. Surprised that it doesn't need much front camber, perhaps down to the jumbo ARB.

Ended up winding up the dampers to full stiff front and rear, at which point the car was handling pretty well. Just a hint of high speed oversteer. Took a couple of clicks off the front dampers but a late red flag meant that I didn't get the chance to try it. Nonetheless, looks like I need stiffer front springs, as running dampers at the max is a sign of overly soft springs.

As expected, the inside rear wheel likes to spin up, even on medium speed corners like Palmer. I'm only on 225 rear tyres but even if I go to 255 I reckon I'll still have the problem on low speed corners. Looks like a LSD is essential. A shorter final drive would be nice, too.

Barely got a clear lap in all day, but looking back at the video, I found a 2:19. I think the car is faster than that. It'll need to be.

Liam22 · Post by **Liam22** » Sat Jul 13, 2019 11:15 pm

Forgot to mention - I was able to run the car over the scrutineering weighbridge.

Front axle 691.5 kg
Rear axle 670.5 kg
Total 1362 kg

That's on a full tank, so ~40 kg of fuel. Encouraging when it comes to stripping the car later. And 50.8 / 49.2 (f/r) weight distribution - that engine doesn't weigh as much as it looks.

Darkangelv2 · Post by **Darkangelv2** » Sun Jul 14, 2019 8:22 am

Sounds like a great first day for understanding your car

I find it really interesting to read the care and attention you guys put into a track day - preparation and maintenance checks during.

I’m definitely taking notes!

Liam22 · Post by **Liam22** » Tue Jul 16, 2019 8:32 am

Leesfarm07 wrote: ↑Wed Jul 10, 2019 8:34 pm thank you

I may have been premature to recommend the paint. It discoloured on my first track session. Mind you, back in the paddock the front discs were still over 275⁰C so perhaps not an issue for road cars.

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enuff_zed · Post by **enuff_zed** » Tue Jul 16, 2019 1:02 pm

Liam22 wrote: ↑Sat Jul 13, 2019 11:10 pm
Crammed the boot full of tools and spares and headed off to Snetterton for a shakedown track day

Hey, if you ever head to Snetterton again, let me know please. I only live 3 miles away and would be interested to come and have a look-see

Liam22 · Post by **Liam22** » Tue Jul 16, 2019 8:02 pm

Snetterton is my local track so I do my testing and setup there.

Usually I post stuff ahead of time, but things have been extra-crazy lately...

Coming back to what I wrote back in February:

Liam22 wrote: ↑Sat Feb 23, 2019 8:42 pm My plan for the build is this:

1. Brakes, suspension, bushes, all fluids, etc
2. Take it for a run around the Nurburgring while it's still road legal
3. Strip, roll cage, race safety equipment

I head off for the Nurburgring on Sunday

Jembo · Post by **Jembo** » Tue Jul 16, 2019 8:26 pm

I

Liam22 wrote: ↑Sat Jul 13, 2019 11:10 pm Nevertheless, looks like I need stiffer front springs, as running dampers at the max is a sign of overly soft springs.

You’ll have to check they fit, but my new eibachs will be coming off my M in August/sept as they are too hard n low for Kent roads

Welcome to make me an offer

J

JDavis21 · Post by **JDavis21** » Mon Jul 22, 2019 3:49 pm

Liam22 wrote: ↑Tue Jul 16, 2019 8:02 pm I head off for the Nurburgring on Sunday

Enjoy it! I managed 5 laps last week, and coming from the MINI - the Z4 felt so composed.

I plan a few more updates later this year, mostly to remove some weight. But shall be booking a trackday or evening at Snetterton when it's ready, as it's only 45 minutes from home, and round the corner from work.

A 2:19 is okay, given the fact barely any weight has been stripped yet and it was your first day in the car.

Liam22 · Post by **Liam22** » Mon Jul 22, 2019 6:02 pm

First time at the 'Ring. What a place! I've driven every race track in the UK, and a few in Europe (including Spa) but the Nordschleife is like no other.

Indicated 150mph into T1. Hitting the bump stops all the way down the main straight over the bumps. Quite frankly, its terrifying.

8:20 BTG on my last lap of the day, and I was taking it easy because I have some grumbling from the rear brakes. But I'm a long way from knowing my way round.

Darkangelv2 · Post by **Darkangelv2** » Mon Jul 22, 2019 6:59 pm

8:20 is no slouching!

JDavis21 · Post by **JDavis21** » Tue Jul 23, 2019 1:57 pm

Liam22 wrote: ↑Mon Jul 22, 2019 6:02 pm First time at the 'Ring. What a place! I've driven every race track in the UK, and a few in Europe (including Spa) but the Nordschleife is like no other.

Indicated 150mph into T1. Hitting the bump stops all the way down the main straight over the bumps. Quite frankly, its terrifying.

8:20 BTG on my last lap of the day, and I was taking it easy because I have some grumbling from the rear brakes. But I'm a long way from knowing my way round.

8:20's damn good going with stock power and weight! Makes me want to do a trackday next time I go, was being quite cautious during my TF laps and always had a passenger with me.

Sounds like you definitely need some stiffer springs before going back on track! When is the interior strip and cage happening?

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