E89 Tyres profile upgrade

[mr wilks]

What does that mean ?

Wouldn't worry , Kumho's are more than OK unless you want to push things .

Precisely chaps....

As in trackdays where they are likely to be heated through to the max unless you drive way over the speed limit on normal roads & manage that

[SteveSmith]

Have you noticed a bit more roll on initial turn in? Maybe it's in my head but it's doesn't feel as direct. I'm seriously considering some Eibach springs to firm it up again.

235 on front 8j style 326 is not going to help the roll feel , you could drop to 215 on that rim width to tighten things up with a 40 profile ?
There are so many differentials here that no exact spec numbers can be said to be the perfect ones whether E85 or E89
Within this post other owners have mentioned arch rub ?
Rim width / offset / suspension & even tyre condition being brand new on full tread as opposed to possible 4mm worn ? (Uni RS3s measure close to 9mm )

I'm going see to it now! No rubbing at the moment.

The car is booked in to have the Eibachs fitted on Wednesday. Can't wait!

[mcbutler]

Sorry, but you are incorrect. They are not "too big for standard wheels." I spoke directly to Continental after reviewing their wheel tire fitments (which shows these tires do in fact work perfectly fine on these size wheels) and they confirmed the sizes work just fine. Now, I've driven my car back and forth at speed on Mullholland Drive here in Los Angeles and I can tell you this car, set up the way it is now, is as fast as you'll want to drive on a roadway open to the public. A Z4 with a tuned N54 motor make substantially more hp and far more torque than even a 3.8 Boxster Spyder (which I have driven in the canyons as well) so even if it did give up a little bit in the corners it powers out a lot faster and is faster on the straights. Since you speak with expertise, have you driven a Z4 with this setup to substantiate your opinion as have I?

I have a tuned N54 with 275/30r19 on a 9.5j rear and 235/35r19 on a 8.5j front. It still won't handle better than a Boxster and that's with a larger contact patch and higher performance tyres than you are using.

A Boxster is a sports car, the Z4 is more of a GT. You need something more than fatter sidewalls to keep up with a porky.

Although to be fair their are not many drivers of either porkys or zeee's that can run either car to its handling limit, or be that stupid on a public road. The magnificent handling of all, so called, supercars is academic when used on the road and a good scooby or similar (barf) will thrash a lot of them of them any.

[warmasice]

Can someone help me?

I'm also in this dilemma. Currently on factory 19" 326s. Eibach Pros are being fitted soon with 12mm rear spacers. I'll be changing the rubber, so no more RFTs.

I'll be going up to 255/35/19 at the rear, but not sure about the front? Should I keep the size at 225/35, or go 225/40 or 235/35? should increasing the rear profile mean that the front should be increased too?.. To maintain the same rolling circumference?

My main concern is that I don't want any rubbing if it can be avoided.

I've also noticed the selection of tyres can be limited depending on the size, which is another variable to consider.

[Beeacon]

Can someone help me?

I'm also in this dilemma. Currently on factory 19" 326s. Eibach Pros are being fitted soon with 12mm rear spacers. I'll be changing the rubber, so no more RFTs.

I'll be going up to 255/35/19 at the rear, but not sure about the front? Should I keep the size at 225/35, or go 225/40 or 235/35? should increasing the rear profile mean that the front should be increased too?.. To maintain the same rolling circumference?

My main concern is that I don't want any rubbing if it can be avoided.

I've also noticed the selection of tyres can be limited depending on the size, which is another variable to consider.

I'm following this with interest.

Do you have Msport suspension, warmasice? I think I'll be in the same boat as you shortly, just want to make sure that there is clearance with the M sport suspension.

[Nick9one1]

Its difficult to tell where they are rubbing from that picture. if its the plastic grill I'd be tempted t remove it (doesn't do much).

[warmasice]

Can someone help me?

I'm also in this dilemma. Currently on factory 19" 326s. Eibach Pros are being fitted soon with 12mm rear spacers. I'll be changing the rubber, so no more RFTs.

I'll be going up to 255/35/19 at the rear, but not sure about the front? Should I keep the size at 225/35, or go 225/40 or 235/35? should increasing the rear profile mean that the front should be increased too?.. To maintain the same rolling circumference?

My main concern is that I don't want any rubbing if it can be avoided.

I've also noticed the selection of tyres can be limited depending on the size, which is another variable to consider.

I'm following this with interest.

Do you have Msport suspension, warmasice? I think I'll be in the same boat as you shortly, just want to make sure that there is clearance with the M sport suspension.

Just had eibach pros fitted and 12mm spacers on the rear. Will be going 255/35 rear but wondering about the fronts at the mo!

[warmasice]

Its difficult to tell where they are rubbing from that picture. if its the plastic grill I'd be tempted t remove it (doesn't do much).

I don't have that plastic grill on my car which I thought was strange?? Unless I was being dim?! Is it only the 35i and 35is that have those?