rear wheel spacers....help needed please

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Mugs
Joined: Wed 07 Aug, 2013 01:26
Posts: 341

  Z3 roadster 1.9

rear wheel spacers....help needed please

Post by Mugs »

Hi all,

i have just undertaken a wide arch conversion to my 1.9 and i am now in need of some spacers for the rear wheels.
does anyone know how much wider the wide arch wings are per side over the narrow arch? (i should have put one of each wing on and measured them but i'm stupid and forgot to do it :? )
i have measured where the wheels are now to where i think they should be and i think i need 30mm spacers but this seems a bit much, hence wanting to know the width difference of the wings.
what make of spacer should i be going for? i see a lot on ebay but they are alloy......would you trust alloy spacers?
anyone who has any experience then please help me with some info.... :D
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Southernboy
Joined: Thu 07 Oct, 2010 12:39
Posts: 6436

  Z3 roadster 3.0i
Location: Johannesburg

Re: rear wheel spacers....help needed please

Post by Southernboy »

15mm is a fair fit, 20mm is about the max you want to go, 30mm is a tad OTT. Remember, the thicker the spacer, the furthe out the wheel will be and consequently the greater the leverage on the centerline of the suspension, which in turn means the suspension springs, shocks and torsion bar are placed under increased pressure as well as the inner CV joint at the diff output. All this can have several consequences including broken springs, abnormal wear on CV joints, excessive compression of the shocks and undue pressure on the bushes and mountings of the rear torsion bar. But whatever you do, get decent spacers... Hubcentric is a must. :wink:
"Normal is overrated"
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bazza1966
Joined: Thu 21 Nov, 2013 10:09
Posts: 92

  Z3 roadster 2.8

Re: rear wheel spacers....help needed please

Post by bazza1966 »

I have fitted 20mm to a 2.8 1998 Zed3 wide body and all seems fine unless anybody says different I would say that's the limit they make the wheels fill the arch see link.
http://i1286.photobucket.com/albums/a62 ... aba0d8.jpg

Bazza :D
Bazza (East Dorset)
t-tony
Joined: Sun 21 Feb, 2010 23:17
Posts: 353

  Z3 roadster 2.0
Location: torksey lock

Re: rear wheel spacers....help needed please

Post by t-tony »

I am currently watching a set of staggered hub centric spacers on eBay.com. They are in California, but we go to our villa in Florida in a couple of months so I will buy them while we are there and save shipping costs. Most items are shipped free in the US. Have plenty of luggage allowance to get them home. Good price too at £68.17. These are 2@ 12mm and 2@ 20mm plus 20 new wheel bolts.
"Knowledge and experience are not always the same"
Mugs
Joined: Wed 07 Aug, 2013 01:26
Posts: 341

  Z3 roadster 1.9

Re: rear wheel spacers....help needed please

Post by Mugs »

thanks for the replies.
i will try 15 or 20mm hubcentric spacers. the axle on the 1.9 is narrower than the 2.8 but it should still space out enough to make them look ok.
i will eventually go for a set of Z3M staggered alloys (the M axle is roughly the same width as the 1.9 so they be a perfect fit) but in the interim i will use the spacers.
for those that have fitted spacers, what make have you used? are they alloy or steel? and are they the type that bolt to the hub then the wheel bolts to the spacer or just slide on using longer bolts?
and finally what are your experiences with the above?

thanks
bazza1966
Joined: Thu 21 Nov, 2013 10:09
Posts: 92

  Z3 roadster 2.8

Re: rear wheel spacers....help needed please

Post by bazza1966 »

Mugs got mine of EBay hub centric made from Ally can't remember who made then came with bolts as well :D
Bazza (East Dorset)
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Southernboy
Joined: Thu 07 Oct, 2010 12:39
Posts: 6436

  Z3 roadster 3.0i
Location: Johannesburg

Re: rear wheel spacers....help needed please

Post by Southernboy »

Ally spacers are fine to use provided they are hubcentric...that means the spacer will fit snugly over the hub on the disc of the wheel automatically centering it to the hub and also not allowing it to move off center. Remember one thing though, because you have in effect doubled the number of faces which hold the wheel to the hub, it is advisable to increase the tightening torque of the wheel bolts. Alternately get the spacers which bolt to the wheel hub and then in turn has the wheel bolted to it. In any event, check the correct torque settings for bolting wheels and apply that to the spacer first and then the wheel if using the last mentioned system. If not, increase the tightening torque by at least 1/2 as much again.
If you can imagine the spacer being able to move just 1/8mm on the face of the wheel hub, and the wheel being able to move the same on the face of the spacer, you might get an idea of the potential for failure if these are not well secured... in effect the bolts will be able to flex when going over any minor bump... and on any drive of even a half mile, the number of bumps or movements up and down as weight is applied and released to the wheel, is probably in the hundreds if not more.
"Normal is overrated"
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