E30 wheel offset and other brands with same offset.

Wed Aug 31, 2005 11:32 am

I've just measured the offset on the wheels that came off the 318IS. It turns out to be 20mm. I understand that this is the std offset for the E30s?
There or thereabouts anyway.

What other cars have similar offsets then?

Wed Aug 31, 2005 1:22 pm

Tom....... The offset required is dictated by the rim width on any specific car.
Examples for E30's are:
6" wide should have 38mm offset
7" wide should have 24mm offset
8" wide should have 13mm offset
9" wide should have 0 offset
Obviously, if you go for half inch increments on the width, the offset should change accordingly.
HTH
Stuart.

Wed Aug 31, 2005 1:28 pm

i dont think my steelies were 6" wide n they were et 35...

Wed Aug 31, 2005 1:33 pm

Jhonno wrote:i dont think my steelies were 6" wide n they were et 35...

5.5" probably used a very similar offset to 6". At those widths, it wouldn't be over-critical - as long as you're somewhere near.

BTW - as always, if I'm wrong and someone can correct me, I'll be humble!

Wed Aug 31, 2005 1:47 pm

essbee wrote:Tom....... The offset required is dictated by the rim width on any specific car.
Examples for E30's are:
6" wide should have 38mm offset
7" wide should have 24mm offset
8" wide should have 13mm offset
9" wide should have 0 offset
Obviously, if you go for half inch increments on the width, the offset should change accordingly.
HTH
Stuart.

just the info I needed... but does this mean that 9" fits an E30 without making any changes?

Wed Aug 31, 2005 1:50 pm

No!!!

Wed Aug 31, 2005 1:51 pm

bebecar wrote:just the info I needed... but does this mean that 9" fits an E30 without making any changes?

If you're going that wide, you will have to roll the arch flanges - particularly if you are lowered 40mm or more.

Wed Aug 31, 2005 1:51 pm

i've got 16x7 with an et20 and they just only just fit under the arches. they need a higher offset which would move them in

Wed Aug 31, 2005 1:52 pm

essbee wrote:
bebecar wrote:just the info I needed... but does this mean that 9" fits an E30 without making any changes?
If you're going that wide, you will have to roll the arch flanges - particularly if you are lowered 40mm or more.

he'll have to do more than that imo

Wed Aug 31, 2005 1:54 pm

The correct offset is 35mm, regardless of rim width.

However, it needs to change with rim width or the inside of the rim starts to hit things like the strut legs at the front.

However, because the struts are at an angle, you find that with larger wheels you can increase the offset again e.g. 7J17 wheels with a 35mm offset should fit AND have the correct offset, 7J15 wheels with a 35mm offset would probably foul the strut and so need a lower and thus incorrect offset.

EDIT> sorry, think the iX had 42mm offsets or something.

Wed Aug 31, 2005 2:58 pm

essbee wrote:
bebecar wrote:just the info I needed... but does this mean that 9" fits an E30 without making any changes?
If you're going that wide, you will have to roll the arch flanges - particularly if you are lowered 40mm or more.

Ok... what about 7.5-8 then?

The car already has 9" all around without problems (but with spacers).... and its dropped way more than 40/40.... but I need to get rid of that look....

Wed Aug 31, 2005 5:00 pm

OK thanks for info. I'm a bit mystified. I measured the 16" wheels that came off the IS and found that they'd been machined to a 20mm offset. ie: 20mm from centre of wheel to mounting surface. This is not a standard offset for the wheel according to the manufactuer's website. So someone had machined the wheels I think.

Overall though, what offset is listed for the E30 318is as standard? Must be same as the 325 Sport since it's all MTech suspension?

Wed Aug 31, 2005 5:51 pm

most 318is came with 14 inch bbs or steelies with special hubcaps.

Have a look at on the original bbs wheels it has? i assume u have them? i sold it with them

15inch bbs are et24

Wed Aug 31, 2005 11:04 pm

I sold the 14" wheels ages ago. Just fitted the 15" BBS wheels from the 320 I broke up. Selling the 16" Team Dynamics wheels at the moment.

Thu Sep 01, 2005 8:59 am

So then... I think I've just come across why my wheels catch on the brakes on the front... they r 7.5" wide 16" wheels with an offset of 20 ?

And one of my other wheels is an offset of 25mm ( got it made up to match the set from a 9" wide wheel)... I have to run a spacer on the 20mm offset... I'm running a 6mm spacer... but I'm going to fetch my 5mm spacer sometime this week...

So that is why my wheel was catching... the cool thing is u can run a much reduced offset on the back... or from what I can see there is loads of clearance there

Thu Sep 01, 2005 3:36 pm

a wee thread hijack!

I'm planning on doing the 5 stud conversion, the main reason being I want to fit E36 M3 "sunflower" alloys.

Does anyone know the offset of these and if they'll fit? I think they are different rim widths front and back.

Cheers.

Thu Sep 01, 2005 5:35 pm

what are sunflower alloys petal?

stevin my 16x7 alpinas are et28 and they are very tight to the caliper on the front like 5mm clearance if that.

If u want 16x7.5 wheels to fit on the front they need to be et25 which will fit perfect like the Hartge alloys

Thu Sep 01, 2005 8:02 pm

Simon13 wrote:what are sunflower alloys petal?

like these http://cgi.ebay.co.uk/BMW-M3-WIDE-TRACK ... dZViewItem
Maybe I'm taking out my ass, but thought I read somewhere they are refered to as "sunflower"