wheels again!

[jeremy]

Using the e30 hubs, what is the max wheel and tyre size that can be used in order to get the max height under the rear arch ,and to bring the wheel out to fill the width of the arch.? Help please!

[MartinClan]

Not an easy question because there are so many factors to take into account like wheel offset and tyre profile. Marlin had 17" wheels on their purple demonstrator but with very low profile tyres.

I have bought 16" rims and plan to fit 205 tyres with either a 60 or 55 profile (depending on what I can get). I think you could probably squeeze 225 in but they probably wouldn't fit under the front mudguards.

There are quite a few web sites around that let you calculate the overall diameter of the wheel using the rim and tyre size. For example

http://www.tyresave.co.uk/tyresize.html

I recon a diameter of about 24 to 25 inches is what to go for.

Perhaps we should have a poll! I will start...


205/60/R16
...
...
...



Robin

[Patrick]

I'm using E36/E46 rolling radius size which is a tad bit bigger than the E30. That means on a 15" wheel I have a 205/60/R15 (IIRC E30's are 205/55/R15)

Alloys go up as big as you want them really. Personally I think 16 or 17 is the largest I would go. You have to take into account that generally the bigger the alloy wheel the more it weights. More weight = bad as it's unsprung.

To fill the rear arches I found the E36/46 size fill it out nicely. What I did do is add spacers 3cm per side in my case - you'd have to measure how much space you have available with the wheels you want to us. Offsets are what determine how far out or in the wheel sits.

www.performacealloys.com do H&R spacers (mine are the hub centric offset type, ie bolt the spacer to the hub then the wheels bolt into the spacer and the spacer has a hub which the wheel sits on) which are TUV tested and therefore good quality.

I've seen 225's on the front, red car at Stoneleigh. If they are stretched a bit with a low enough profile I think they should fit. You might get way with 235 or 245 at the back.

1) 205/60/R16 - Robin
2) 205/60/R15 - Patrick
...
...
...
...

[peterux]

I'm currently running 205/50R15's and you've seen what these look like on my pictures.
I have some 16" Borbet alloy's but haven't decided what size tyres to get yet.
The back of the car is no issue, you can almost go as wide as you like. The front mud guards will only take about 215. I have some wider mudguards which are un-fitted.
Not sure what to do about the Borbet's as I am getting quite attached to the look of my Alessio alloys, currently fitted.

1) 205/60/R16 - Robin
2) 205/60/R15 - Patrick
3) 205/50/R15 - Peter (possibly going for 245/45ZR16 or 225/40ZR16)

[jeremy]

This is a great correlation of info-could the offset of the alloys used and spacer info be added?

[Patrick]

Originally Posted by jeremy

This is a great correlation of info-could the offset of the alloys used and spacer info be added?

Pretty much yeah. Those friendly chaps at image wheels would make any size, width and offset you need but they are muchos expensive!

I find the whole thing a bit confusing because as the wheels get wider you need to use different offsets!

One thing I am sure of is that wheels suitable for the E30 should fit fine on the front and need some spacers at the back. Golf/VAG group 4 studs might need spacers front and back I believe.

[MartinClan]

1) 205/55/R16 - Azev Alloys 16 x 7.5J Offset ET20 - Robin
2) 205/60/R15 - Patrick
3) 205/50/R15 - Peter (possibly going for 245/45ZR16 or 225/40ZR16)

Found a good place to get the Yoko tyres. www.mytyres.co.uk - seem to be much cheaper than black circles.

Robin

[Patrick]

A few other places to try (that I've been recommended)

http://www.tyretraders.com/
http://www.camskill.co.uk/

[peterux]

Originally Posted by jeremy

This is a great correlation of info-could the offset of the alloys used and spacer info be added?

Hi Jeremy,
my alloys are ET35 offset (or maybe ET38??) I have 13mm spacers on the front and a whopping 32mm spacers on the back!
regards

Peter

[MartinClan]

I just trial fitted my wheels that now have the tyres fitted.

They fit both front and back without spacers - possibly as the aftermarket wheels are ET 20 not the ET 35 of standard beemer wheels (A bit of luck that)

At the front the (new) wing stays are a perfect fit and the mudguards seem to be correctly positioned without any mods. (Bolt up tomorrow)

At the back I think I might need some small spacers just so the wheels fill the wings - not 100% sure as the wings are off at the moment to give me more room to work around the car.

Robin

[Mike]

[I find the whole thing a bit confusing because as the wheels get wider you need to use different offsets!/QUOTE]

The offset is design to keep the centre of the wheel on the centre line of the steering pivot. Thus if you increase the wheel width by 20mm, the offset will change by 10mm. The rear offset is irrelevant as there is no pivot, but you will change the steering geometry, and handling, if you change the front offset away from the centre line.
Mike

[Mike]

How do you pick the quote in a high:lighted blue box - I still haevn't worked it out!!??!!
And why do I only get words not the smiley icon????

Please help an oldie be IT literate.
Mike

[Patrick]

Originally Posted by Mike

How do you pick the quote in a high:lighted blue box - I still haevn't worked it out!!??!!
And why do I only get words not the smiley icon????

Please help an oldie be IT literate.
Mike

Press the button at the bottom of the post you want to reply to then type your message after the [/quote] bit

Smilies, click "Go Advanced" and there's a pallet of them on the right, just click the one you want and it puts it in where you cursor is in the text

[Mike]

Originally Posted by Patrick

Press the button at the bottom of the post you want to reply to then type your message after the

bit

Smilies, click "Go Advanced" and there's a pallet of them on the right, just click the one you want and it puts it in where you cursor is in the text [/QUOTE]

Thanks Patrick.
Hopefully that's the quoted sorted...but where is the "Go advanced"?

BTW - have you seen your gearstick in my Cabrio?
Regards Mike

[Patrick]

Go advanced you only need to do if your editing a post or are using the "Quick Reply" at the bottom of the page - button next to post quick reply

Not seen the gear stick yet Did you post some pics on here?

[Mike]

Not seen the gear stick yet Did you post some pics on here?[/QUOTE]

Patrick
Photos are on my site:http://www.flickr.com/photos/mikes_b...io/2878136481/
Mike

[Patrick]

Excellent, fits really well

[timbo]

Hi
Its panic stations as my SVA test date has come through for the middle of April and the new wheels I ordered in November still haven't arrived! I had some cheapo 15 inch wheels but they're a bit close to the front brake calipers, so am changing to 16 (x 7.5). Having looked at the previous info, I reckon 215/50 or 205/55 tyres would fit (its an E36 base). Is this right? And is there any reason why one should go for one rather than the other?
Thanks
Tim

[Patrick]

You can use this calculator to compare tyre sizes: http://www.tyresave.co.uk/tyresize.html

Wider tyres will give you more grip round the bends, at the front it will make the steering heavier the wider the tyres are.

I've got 205 width all round which works well, I was think of putting wider ones on the back at some point. I've seen Sportsters at Stoneleigh with 225 width on the front so that should fit under the wing.

I've gone form E30 profile to E36 profile on my Sportster so on a 15" rim its 60% high rather than 55% on the E30.

The only thing you need to do it match the speedo to the rolling radius

[timbo]

Thanks Patrick