Liam's Z4C race car project

NeilP · Post by **NeilP** » Tue Dec 24, 2019 1:55 pm

So envious of this build! Great progress so far!

Vanne · Post by **Vanne** » Mon Jan 27, 2020 6:34 am

Hows it going Liam, any headway mate?

Tamir · Post by **Tamir** » Mon Jan 27, 2020 11:59 am

How's it coming along nowadays Liam?
Looking great so far even though there's no way back as it seems

Liam22 · Post by **Liam22** » Tue Jan 28, 2020 12:40 am

I was going to post an update today anyway, but thanks for the prompt!

Picked up the car from the roll cage fitter on Thursday. This is the basic Custom Cages 6-point weld in cage, designed for the roadster but fits the coupe just fine. Ridiculously expensive for what it is, but cheaper than a bespoke cage.

I added a few upgrades for stiffness and safety:

Diagonal across the main hoop (behind the seats)
Harness bar / rear strut brace (another benefit of removing the false bulkhead)
Tie-in points on the A-pillar and upper windscreen area

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The other custom work was to create a secure frame to mount the seat onto. So we have two lateral tubes welded into the body, and longitudinal mounting brackets with adjustments.

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Got it home, cleaned the interior and took it straight to the paint shop. I chose a light grey from the RAL colour chart. The end result is a little lighter than I wanted, but it's OK.

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It's great to have it back, but there's a ton of work to do putting everything back together.

MrPT · Post by **MrPT** » Tue Jan 28, 2020 8:16 am

Tamir · Post by **Tamir** » Tue Jan 28, 2020 10:00 am

Professionally done!

Vanne · Post by **Vanne** » Tue Jan 28, 2020 11:48 am

Looks awesome Liam, and well worth the wait mate.

I actually quite like the colour youve gone for, looks clean. exellent welding job , those seams look very nice indeed. How does it work over where you are? do you have to get FIA certification for the welding?

You just got me psyched up do do some more cable work on my car.

standing by while you piece it all back together.

exellent progress.

Beedub · Post by **Beedub** » Tue Jan 28, 2020 4:24 pm

amazing!!!

DaveD · Post by **DaveD** » Tue Jan 28, 2020 10:00 pm

Great to see Liam... good progress. Whilst you have been doing all of this, I managed to get under my car eventually last weekend to fit that rear arb I bought off you! Only take about 4 months....

Liam22 · Post by **Liam22** » Tue Feb 18, 2020 9:22 am

Got started on re-assembly.

Fuel tank back in. Wiring pulled through, tidied up, and wrapped in trunking. Was quite pleased when the car started but I have plenty of lights on the dash, including engine warning. I'll need to get a code reader on it, but there's no exhaust fitted at the moment and I don't want to upset the neighbours by running it for very long.

An unexpected hiccup was that the new seat mounts are in the way of where the ABS sensor sits. Modified the bracket so that I can hang it from the seat mount instead. Carefully measured the distance to the cross member so that it is still "square" in the car.

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Made a new floor to take up the space where carpet should be. This is 6mm aluminium composite sheet which is stiff and light. I'll add some skateboard grip tape to avoid slippage. I may also need to bring the footrest further forwards but will wait until I've actually got the seat back in before deciding if I need to make adjustments.

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The dashboard received some "butchery" to get it back in. Always difficult trying to remove the minimum amount to clear the roll cage while still leaving enough meat to mount securely. I also removed the entire inlay area, which will be replaced with a full width panel to mount switches, fire extinguisher handle, etc.

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With the dash back in, I can now go about getting the windscreen replaced/refitted. Tempted by a heated item to avoid having to fit a custom demist solution.

The next big job is to overhaul the differential with a Kaaz 1.5 way LSD. Need to order new seals and bearings next.

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The BMW TIS is typically useless when it comes to actual instructions for rebuilding the diff and measuring backlash etc. Does anyone have any pointers for the real workshop manuals?

Vanne · Post by **Vanne** » Thu Feb 20, 2020 12:12 am

Awesome updates.. keep em coming mate. Looking really good. Yep, it's hard cutting the dash. Difficult to measure exactly where to cut.

Nice LSD. How are you getting on with that? Getting mine done, it's out of my league.

Liam22 · Post by **Liam22** » Thu Feb 20, 2020 10:30 am

Turns out BMW don't even supply bearings for these diffs. Looking at aftermarket options now.

Vanne · Post by **Vanne** » Thu Feb 20, 2020 11:17 am

Which diff have you got? They don't, that's true, but with a bit of investigate sniff work you can figure it out. I plugged together a kit of my own. Though I did fluff up one or two of the bearings, which someone happily pointed my nose at. It's Def do-able. If you have the m diff, I can give you the part numbers you'll need.

Liam22 · Post by **Liam22** » Thu Feb 20, 2020 11:54 am

It's the medium case, 188K. These guys are local to me:

https://www.bearingkits.co.uk/BMW-Z4-E8 ... IT/941.htm

Vanne · Post by **Vanne** » Thu Feb 20, 2020 12:55 pm

Awesome! That's good work, making it easy.

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