Race Build Z3 roadster

Tyres, exhausts, suspension, strut braces, air filters, brake pads/rotors and anything else for 'dawn raiders'.

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TheStorm
Joined: Tue 12 Feb, 2019 13:24
Posts: 22

  Z3 roadster 1.8

Race Build Z3 roadster

Post by TheStorm » Wed 13 Feb, 2019 09:27

Hi all!

So, I will be grateful for any tips and tricks you have for race build Z3.
The idea currently is to be street car for 2019 and if does good this year... will be full race mode 2020.

So, up to now:
- Z3 1996 1.8 115hp car... was ( and actually still is) my daily for 2 years
- M52B28TU swapped with gearbox and drivetrain from the m43 (4cyl)
- will receive m54b30 intake cam and some mild remap... but power ideas are welcomed.
- 3.45 small case LSD but I am preparing big case LSD... just thinking if 3.46 is good ratio or I should go shorter???
- full poly bushing everywhere
- full e46 suspension in front - very nice wide body
- 300mm front brakes in front (e46) I guess these will do the job, because the 325mm are a bit heavy
-stock z3 solid disks on the back - maybe upgrade here???
- some e46 coilovers. Will be glad if you throw me ideas what spring ratios will work good.
- e36 25.5mm front strut and stock rear strut (I think it is 14mm? I expect understeering... some ideas here???
- in couple weeks my fiberglass hood and front bumper will arrive ... they are in progress
- bucket seat is available... need to fabricate spacers. Will be gladful if someone has sketch for such. Second same bucket should be installed for weght reduction. And with nice seat belts

Currently I have set of Style 66 8J/9J 17" that will be with 235/40/17
And set of some other brand rims 8.5J / 10J that are with 245/40/17 ... but could go with 255s on the back.

Currently it weights 1223kg with 15" steelis, but with new hood and buckets I hope under 1200

So... any ideas for better time and more stable car are welcomed. And any experience with suspension setup will be greatly appreciated!

Pics with the 17s 8.5/10J... and from last summer with e36 suspension and style 66s

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Thank you!

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stevov
Joined: Sun 21 Dec, 2014 15:56
Posts: 182

  Z3 roadster 2.0
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Re: Race Build Z3 roadster

Post by stevov » Thu 14 Feb, 2019 12:30

I may be wrong but wheels protruding from the wheel arch are illegal so arches need to be extended. On staggered wheels tyre sizes are different front to rear to preserve rolling radius ie 225/45/17 front 255/40 17 rear

TheStorm
Joined: Tue 12 Feb, 2019 13:24
Posts: 22

  Z3 roadster 1.8

Re: Race Build Z3 roadster

Post by TheStorm » Thu 14 Feb, 2019 12:35

Yes, as I wrote - I am waiting for the wider front hood. I have to be wider because it is touching the hood right now. (and the under arches)

Also - found one rear left widebody wing... in search of right one ... anyone? so I can be lower and wide.


About the staggered set - yes .. I might go for 255 on the rear .. just currently I have these and doing some tests with them.

245/40/17 and 255/40/17 might be enough for the not-so-heavy Z :)

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stevov
Joined: Sun 21 Dec, 2014 15:56
Posts: 182

  Z3 roadster 2.0
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Re: Race Build Z3 roadster

Post by stevov » Thu 14 Feb, 2019 12:54

Different rolling radius can affect abs and traction control

TheStorm
Joined: Tue 12 Feb, 2019 13:24
Posts: 22

  Z3 roadster 1.8

Re: Race Build Z3 roadster

Post by TheStorm » Thu 14 Feb, 2019 15:22

I don't have traction ...

ABS is very stupid on these cars .. so it wont be affected..


BUT in general speaking .. difference in speed in front to rear tyres is exactly how the smart systems detect aquaplaning .. but we are speaking of smart traction controls here :)

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stevov
Joined: Sun 21 Dec, 2014 15:56
Posts: 182

  Z3 roadster 2.0
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Re: Race Build Z3 roadster

Post by stevov » Thu 14 Feb, 2019 15:52

:thumb:

Juvvajuvva
Joined: Sun 06 Nov, 2016 16:52
Posts: 75

  Z3 roadster 2.8

Re: Race Build Z3 roadster

Post by Juvvajuvva » Sat 16 Feb, 2019 19:37

I have 275 40 18 rear r888 GG compound on 10j and 235 45 17 front r888 SG (softer compound) on 7 1/2 J.
Scuttle shake is your enemy. Front strut brace, rear Bertini and also a Hardog roll bar on order.
Full coil over set up, KW variant, poly bushes all round, near solid engine mounts, camber adjustable rear trailing arm bushes, BBK and the list goes on.
67mm throttle body and TRC , s50b32 manifolds and Z3m full twin cats and cans. Twin lambda ecu conversion set up, stage 2 tune with standard cams.
You can get more power with USA cams but the power curve is later and less road friendly.
Good luck and enjoy your build.

Juvvajuvva
Joined: Sun 06 Nov, 2016 16:52
Posts: 75

  Z3 roadster 2.8

Re: Race Build Z3 roadster

Post by Juvvajuvva » Sat 16 Feb, 2019 19:38

Oh yeah, dump the ABS.

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motco
Joined: Tue 18 Aug, 2009 19:12
Posts: 685

  Z3 roadster 2.2i

Re: Race Build Z3 roadster

Post by motco » Sun 17 Feb, 2019 09:42

stevov wrote:
Thu 14 Feb, 2019 12:30
I may be wrong but wheels protruding from the wheel arch are illegal so arches need to be extended. On staggered wheels tyre sizes are different front to rear to preserve rolling radius ie 225/45/17 front 255/40 17 rear
OP's domicile is Bulgaria according to the flag in his details, so perhaps protruding wheels may not be a problem?

TheStorm
Joined: Tue 12 Feb, 2019 13:24
Posts: 22

  Z3 roadster 1.8

Re: Race Build Z3 roadster

Post by TheStorm » Mon 18 Feb, 2019 08:08

motco wrote:
Sun 17 Feb, 2019 09:42
stevov wrote:
Thu 14 Feb, 2019 12:30
I may be wrong but wheels protruding from the wheel arch are illegal so arches need to be extended. On staggered wheels tyre sizes are different front to rear to preserve rolling radius ie 225/45/17 front 255/40 17 rear
OP's domicile is Bulgaria according to the flag in his details, so perhaps protruding wheels may not be a problem?
Nice one!

Yes, I am in Bulgaria and a lot of details about the car are not exactly legal. For example - the engine swap. (please dont tell the cops :) ) But I still believe that the car is in progress and will do my best to be nice looking (and more legal) soon.

Still looking for performance hints.

May something about power?
the engine is M52B28TU, with sport exhaust headers and 2x50mm to the end. I will put intake camshaft from M54B30 and maybe will put exhaust camshaft with 240' duration. And some remap of the ECU.. but something more I can do?

TheStorm
Joined: Tue 12 Feb, 2019 13:24
Posts: 22

  Z3 roadster 1.8

Re: Race Build Z3 roadster

Post by TheStorm » Thu 21 Feb, 2019 10:38

WIDEBODY UPDATE :

So .. finally the one wide wing arrived. I am VERY pleased with the tests :)

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And here I have test fitted 10J Et17 with 245 40 17:

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So I can go even wider with 255s on the back, thinking of small spacer also. This will be WIDE :lol:

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stevov
Joined: Sun 21 Dec, 2014 15:56
Posts: 182

  Z3 roadster 2.0
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Re: Race Build Z3 roadster

Post by stevov » Thu 21 Feb, 2019 12:25

I ran 255 with a 15mm spacer just fine

TheStorm
Joined: Tue 12 Feb, 2019 13:24
Posts: 22

  Z3 roadster 1.8

Re: Race Build Z3 roadster

Post by TheStorm » Thu 21 Feb, 2019 14:39

stevov wrote:
Thu 21 Feb, 2019 12:25
I ran 255 with a 15mm spacer just fine
what were the specs of the rims?

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stevov
Joined: Sun 21 Dec, 2014 15:56
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  Z3 roadster 2.0
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Re: Race Build Z3 roadster

Post by stevov » Thu 21 Feb, 2019 15:09

Staggered 17” 68’s

TheStorm
Joined: Tue 12 Feb, 2019 13:24
Posts: 22

  Z3 roadster 1.8

Re: Race Build Z3 roadster

Post by TheStorm » Thu 21 Feb, 2019 15:46

7,5 / 8,5 from E46?

They are with Huuuuge ET ....


This is 8,5 J With 255 40 17:

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stevov
Joined: Sun 21 Dec, 2014 15:56
Posts: 182

  Z3 roadster 2.0
Contact:

Re: Race Build Z3 roadster

Post by stevov » Thu 21 Feb, 2019 16:25

Only pic I could find oops didn't work. Wheels fit well and looked good

TheStorm
Joined: Tue 12 Feb, 2019 13:24
Posts: 22

  Z3 roadster 1.8

Re: Race Build Z3 roadster

Post by TheStorm » Mon 25 Feb, 2019 08:16

I think I found also a right one ... we will see ...


In the meantime - when every gram counts :lol:

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P.S. I got a call from Porsche Classics - they want the drill back :lol: :lol:

TheStorm
Joined: Tue 12 Feb, 2019 13:24
Posts: 22

  Z3 roadster 1.8

Re: Race Build Z3 roadster

Post by TheStorm » Wed 27 Feb, 2019 08:50

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Of course the front one got drilled also :D

I have delay in the fiberglass front bumper and hood ... I am still waiting them .. but .. the will be ready in March and after that will see how much this weights

TheStorm
Joined: Tue 12 Feb, 2019 13:24
Posts: 22

  Z3 roadster 1.8

Re: Race Build Z3 roadster

Post by TheStorm » Wed 06 Mar, 2019 10:54

Sadly.. still waiting for a lot of parts to arrive.

in the meantime I have serious thoughts what suspension to use.... As I mentioned - in the from I am with everything from E46 (hub, brake disk, wishbone.. )


So .. any suggestions for coilovers in the sub 1k EUR/GBP range? (or more, if they accept to sponsor me :D )

TheStorm
Joined: Tue 12 Feb, 2019 13:24
Posts: 22

  Z3 roadster 1.8

Re: Race Build Z3 roadster

Post by TheStorm » Mon 18 Mar, 2019 09:12

So.. some updates :


1. My new LSD came. 3.91, type 188. Sorry.. I think I have no pictures... BUT - tree new friction discs, new mirror discs and the acceleration ramps are with bigger angle - so it is 1.5 WAY now .. for better locking

2. I put big half shafts from E30 (I had them laying in the garage). They fit fine, but the ABS rings are bigger than the Zs. I had about 2mm spacer to raise a bit the ABS sensor and the half shafts went in without troubles. I have NOT driven the car yet to confirm if ABS works .. will check and update
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3. Changed the oil pipe feeding the vanos. It seems that this is the reason for oil on my engine.

4. Put the wide fenders in the back. Finally the right one came and everything looks good. So now a wheel 10J ET17 with 245/40/17 looks .. small inside the fender :D :D

5. disassembled the whole left side.. there was a LOT of dirt inside the side skirt .. and inside there... The car and the engine deserved a good bath

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6. FINALLY - my lightweight and wide hood and front bumper came! I am stunned how WIDE this car can be :D :D :D Note, that in these pictures the car is with the wide rear fenders, and the front wheels are 8.5J Et20 with 245/40/17. Currently they are just put there .. I have a lot of work to fit them correctly, but it looks very good and promising.

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TheStorm
Joined: Tue 12 Feb, 2019 13:24
Posts: 22

  Z3 roadster 1.8

Re: Race Build Z3 roadster

Post by TheStorm » Thu 21 Mar, 2019 08:31

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So.. 8,5J with ET -7 (minus 7) looks good in the front. The front step is wider than the back .. this should help tight cornering.

I have some troubles correctly fitting the front bumper .. I am considering tube frame. Hopefully I will finish it before 30th. We have trackday where I really really want to go and first test the car.

TheStorm
Joined: Tue 12 Feb, 2019 13:24
Posts: 22

  Z3 roadster 1.8

Re: Race Build Z3 roadster

Post by TheStorm » Tue 16 Apr, 2019 14:13

So, a little bit of update.

I finally fitted a bit the front end. I have now also 20mm spacers on all wheels and the fitment is now much better

It is finally start looking like a car again :lol:

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And one harness .. to hold me down:

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TheStorm
Joined: Tue 12 Feb, 2019 13:24
Posts: 22

  Z3 roadster 1.8

Re: Race Build Z3 roadster

Post by TheStorm » Mon 22 Apr, 2019 08:15

Finally, I managed to paint it a bit ... not perfect, but I did it myself and did it in front of the garage :lol:


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Gazza
Site Admin
Joined: Tue 04 Oct, 2005 21:58
Posts: 9416

  M roadster S54
Location: Romford Essex

Re: Race Build Z3 roadster

Post by Gazza » Mon 22 Apr, 2019 12:53

Coming together nicely
Gazza

"Understeer is when you hit the wall with the front of the car, oversteer is when you hit the wall with the rear of the car. Horsepower is how fast you hit the wall and torque is how far you take the wall with you"

Z3 S54 M roadster Image, BMW Z1, BMW M3 CSL, Z4M Coupe
ImageImage

TheStorm
Joined: Tue 12 Feb, 2019 13:24
Posts: 22

  Z3 roadster 1.8

Re: Race Build Z3 roadster

Post by TheStorm » Tue 11 Jun, 2019 10:00

Hi again,

I had one time attack event already. I am VERY pleased how the car drives and goes on the track... but of course .. I am looking for upgrades already :D

So I borrowed one wheel from a friend to test

The wheel is 18" 10.5J ЕТ25 with 270mm slick tyre. I am with 20mm spacer so effective ET is 5

Front :
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Back:

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So.. I have sold already my 17" and I am looking for wide 18" rims .. Thinking of 265 35 18 / 285 35 18 semi slicks

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