5 Lug Rear hubs

[JakeusSnakeus]

I'm finding it difficult to get my hands on some Z3 3.0l rear hubs for my 5 lug swap, Rear arms are 325i.

Am I right in thinking I need 33411095772

(Part number 1)
http://www.realoem.com/bmw/enUS/showpar ... Id=33_0458

[Supafly]

Before you go down this route, have a search for z4 hubs, I believe they press into standard e30 trailing arms and are only 2.5mm wider than standard which means you don't have to search for crazy ofset wheels to suit.... If I find the link when I get home I'll post it here.

[JakeusSnakeus]

Ok thanks, Z4 bits should be much easier to source.

So are the Z3 3L hubs significantly wider than the E30 ones?

[Supafly]

I'm not sure about the 3.0 ones but I think the z3 hubs add about 25mm per side.

See r3vlimited thread for more info.... z4 hubs on e30

https://www.r3vlimited.com/board/showth ... p?t=325258

[blazed]

If you click the part number it shows that the hub is used on all z3 models except for the z3m.
http://www.realoem.com/bmw/enUS/partxre ... &series=Z3

[JakeusSnakeus]

I'm not sure about the 3.0 ones but I think the z3 hubs add about 25mm per side.

See r3vlimited thread for more info.... z4 hubs on e30

https://www.r3vlimited.com/board/showth ... p?t=325258

I thought they only added 25mm if you are using the Z3 Trailing arms? Which I'm not...

[JakeusSnakeus]

On that German forum it says:

Wheel Spacer (per side)

E30 hub ---- 0mm

Z4 hub ----2,5mm

M3 E30 hub ----5mm

E36 323ti Compact hub ----19mm

And i think that is based on using the E30 Trailing arms

[Supafly]

Yes I believe that it is based on standard e30 trailing arms. I have a 325i which I am planning to go 5 stud on using these hubs with e46 328i rear discs.

I'm not sure about the z3 hubs on e30 trailing arms, I think it still keeps the greater offset???

[B5234FT]

I've been looking into this a lot recently, and I've just broken a widebody Z3 for the parts.

The hubs themselves definitely add offset, they're clearly wider than the E30 items, resulting in a much deeper bell on the disk







Compared to

http://e30performance.info/viewtopic.php?t=623

or



An E30 has a 1415mm rear track width
https://www.carfolio.com/specifications ... ?car=31163

A Z3 widebody has a track of 1494mm
https://www.autoevolution.com/cars/bmw- ... 3-1996-18i

So an increase of 80mm, but the wheel offset also changed from ET20 to ET38, so with the same wheels that increase would have been more like 116mm. I'd guess there is 20mm in each hub assembly and 35 in each arm or thereabouts.

One can get away with the z3 hubs on the E30 arms by using the higher offset wheels without any increase in track width, but cant get away with fitting the complete arms because they are much wider.

What I want to look into next is the Z4 hubs as these should allow the use of more reasonable offsets, but because these hubs (and their assosciated disks) come from models with multilink suspension, the disk/drum/caliper takes a bit more effort.

[Supafly]

I already have the epytec sleeves for the front's which will allow me to use e46 front hubs.

For the rear I too have been researching for a while now, the current 'plan' is to use z4 hubs with e46 328i rear discs which should in theory allow me to keep existing brake shoes with a larger diameter disc to balance the front.

More information... (no association but there is some very useful info here and user ngampleh has been very helpful in answering my questions. I will probably be buying his rear brackets for my above solution)

https://www.r3vlimited.com/board/showth ... 5&t=400005

[Supafly]

Thank you for the info and clarification B5234FT

[B5234FT]

Yeah I've been reading that same thread, but everyone seems desperate to fit massive vented rear disks to an E30, which seems a touch unecessary.

I'm hoping to use the standard Z3 calipers if I can.

[JakeusSnakeus]

Thank you for the info and clarification B5234FT

-- I 2nd that thanks

I stumbled across that post with the adapters a while back too, they look good but on the back its just a bracket so nothing you couldn't have someone knock up i guess. Glad there are a few of us in the same boat though if anyone is interested in doing a bulk order of those adapter plates?

Here's my intended setup anyway:

(don't lynch me on the ott brakes lol it is a race car)

Front:
E36 M3 Spindles
E36 M3 Hubs
Probably AP disks and calipers (OEM E36 M3 Evo bits for sale)
E36 M3 LCA's
Offset LCA bushings

Rear:
E30 325i Trailing arms
z4/e90/e92 hubs - 33416752381 - (x2)
e30 rear wheel bearing - 33416762317 - (x2)

Rear brakes wont be OE either so guess ill have to see what i can get to fit. I'm guessing with a set of those brackets i can just buy a big brake kit that will fit an E46? What do you guys think??

[B5234FT]

To be honest, with that spec, you have a number of different priorities.

First off, for a race car you wont need an MOT, or a mechanical handbrake, so instead of trying to use off the shelf BMW drums.

Secondly, you'll likely want larger brakes than most, but smaller than race sized E46 stuff.

I'd be either going for alloy belled disks or vented BMW stuff and a nice alloy 4 pot personally and then a custom adaptor.

If you're making an adaptor anyway, allsorts is possible. The difficulty is finding a bolt on OEM solution which retains the handbrake for tuned road cars.

[Supafly]

It's really worth taking the time to understand brake balance too. There are lots of posts online that explain the calculations and plenty of on line calculators too.

It is very easy to ruin the braking of the car by changing components without regard to balance. Even setups that have high initial torque may feel better but can overall be worse.

A well functioning standard set up is very very good even with 230bhp. I have previously refreshed the whole system and run ferodo ds2500 pads all round. This was a very good set up that I wasn't able to fade, although i did induce cracking in the discs which I could have minimised with better cooling. Cold braking was not as good as standard though.

For me I am planning to turbo charge and have approx 400 bhp. To try and keep this in check I am going to install the full e46 set up including master cylinder to maintain oem balance, which in the e30 will leave an over braked rear. I am also installing the mk60 ABS that will ensure I don't lock the rears up too early and will mitigate the extra braking in the rear and hopefully maximise brake effort from all four corners.

I plan to run oem pads to keep the cold bite up (something that was lacking with the ferodo ds2500 set up) and run more directed cooling to the center of the discs and pads to keep them from over heating. Mine is mainly a road car, if I was to track the car I will swap out to better pads. This I think will be ideal for my expected usage of the car.

As B5234FT has said it is worth optimising your set up for your intended usage, that way you'll minimise any compromises you will need to make and have the best set up for you.

[JakeusSnakeus]

I'm going to be limited to what i can get under some 17" wheels anyway, i don't think 18's are realistic in this scenario without tub work. Plus they'll look stupid. Balance shouldn't be too much of an issue as i'm running a pedal box with individual master cylinders and a bias bar. I hear what you're saying though Supafly, facts over bro science so I'll do some further research.

Just to give you an idea of what other people in my series are running, all be it a heavier car at around 1400 kg....





my e30 stripped with cage, full glass and electrics came in at 1150 kg before but its been on quite a significant diet of fibreglass and lexan since along with ditching the steel fuel tank and a host of other things so i'd love it to be in the 1000 kg region but we'll see.

[B5234FT]

Pedal box or no pedal box it's better to have the bias correct with the brake spec than to hobble one end with low line pressure.

Not only does it reduce the disk inertia which aids acceleration, and the unsprung weight which aids cornering grip, it also makes it easier to specify pads if the heat ranges are similar