Ideal sized wheels for handling

[MarkT]

As in the title really. What is the best size wheel for optimum handling for an E30 15's? Need to know as the 340's going to be track orientated.

[scootlife]

Alpina and Hartge went for 16's and I believe they did that for a good reason rather than just looks..

[Felix79]

all the tuning houses use to put 16"s on

[MarkT]

Sounds fair enough to me thanks guys

[scootlife]

Doesnt the M3 have 16's also ???

[Felix79]

yup , like I said all the tuning houses from Alpina to BMW's M division put 16"s on

[monkey]

didn't m3s come with 15"s on standard ?

[Felix79]

5 stud 16" IIRC

[sweep]

Some come with 15s on as davekp's on here has..

[DanThe]

didn't m3s come with 15"s on standard ?

Yes.

I had 16's on my E30 for over a year, then changed to 15's and the handling changed more than I expected

[Felix79]

your right. I think the Evo onwards had the 16"

[monkey]

didn't m3s come with 15"s on standard ?

Yes.

I had 16's on my E30 for over a year, then changed to 15's and the handling changed more than I expected

do you mean it was worse on the 15s

[fuzzy]

Alpina and Hartge went for 16's and I believe they did that for a good reason rather than just looks..

you surely cant be suggesting bmw compromised on something?

[DanThe]

The steering felt better on the 16's, probably due to the offset difference

[Rav335uk]

It would also come down to the profile of the tyre too

[DHFiS]

Was the M3 not 15" from the factory?

[Falkster]

Yeah they were. Evos etc came with 16s.

Ideal size is 16 IMO, Ive got 18" M Parallels on my M3 at the moment and it doesn't handle anywhere near it should.

[cirrusloon]

The likes of suspension on M Power and Alpina cars are completely revised compared to the standard E30 in order to accomodate larger wheels. Just slapping some on your car doesn't mean you will instantly get the same benefits. There's a lot of synergy amongst the set-up of the car as a whole.

Lowering the profile of a tyre by moving up a rim size will reduce deflection in the tyre sidewall, providing a firmer ride and increased steering response. This can also translate asa crashier ride which is dialled out with the suspension mods etc.

15's are the best bet straight out of the box. Moving to a 16" rim will get you many benefits if you're prepared to put work into other areas of the car.

[dips346]

8x16 " with very good tyres

[Jhonno]

I am a fan of how mine handles on 17's..

It is almost as much about the tyre choice and quality of the wheel (weight etc) as the actual size of the rim..

The bigger wheels require lower profile to retain rolling dia = Sharper turn in, reduction in ride quality, higher limits, but less warning when you reach them

Ride quality on mine with 350/580 springs and 215/40 tyres is more than acceptable!

[Grrrmachine]

If Alpina used 16" rims, what profile tyres did they couple that with? And if you were to use 15s, what profile would you need to raise the diameter up to Alpina size?
This is presuming tyre technology has advanced enough in 20 years to remove a certain amount of sidewall flex, of course.

[Rav335uk]

Alpina used 205/50/16 on the fronts and iirc 225/45/16 on the rears

[Grrrmachine]

Which means a 15" rim would need a 205/60 tyre on the front and a 225/55 on the rear. Not too hard to get hold of.

[M3Jim]

The early DTM cars used 17 inch wheels, and the later cars used an 18, hence the evo 3 had larger front wings than the standard m3,so they were allowed larger rims, now i'm sure these boys knew what they were doing. And being the most successful touring car ever, I guess they did. Just because they used smaller wheels on the road car doesn't generally mean they handle better.

I think it's more a case of the tires being cheaper and easier to come by in a smaller size.
I have both 16 with 225 45 and 17 with 235 40 for my m3, to be honest there is not much in it, the smaller walls of the 17 and being wider does makes it more responsive tho.

Plus 16's just don't fill my arches enough for me

[e301988325i]

I read that wheels should be the smallest size that fit over the required brake set up, from a handling point of view. . . check the motorsport threads on here and see what others are running

[blue30]

Cars built for a smooth track tend to have big wheels, cause they can fit big brakes under them and run lower profile tyres etc. Which they can get away with cause the suspension's so stiff as well.

On a road car I think you need quite a bit of give in the tyres because the suspension has to be that much softer, meaning that the geometry moves around that much more meaning that the tyre has to take up the difference to stay on the road across the full width.

If that makes any sense!?

[Black_Potato]

"handling" wont be effected in a huge way by rim diameter and normally this will have just been for looks, however weight and tyre choice will have a huge impact on handling.

So.. Weight and range of tyres availbale should be your key drivers & given that 15" tyres are cheap and easy to come by I'd go for them rather than buy 17" rims and stick crapalto brand tyres on them.

Obviously if you can afford drop forged rims and £1000 a set rubber then your choices are limitless.

[MarkT]

Thank's for all of the feed back guys, interesting reading. I thing froms a financial point of view i'll run 15's with 205/60/15 and 225/55/15 tyres. It's easy enough to pick up cheap tidy rims and also tyres too.

[Morat]

Those sizes are bigger than stock, ideally you'd want 205/55/15 all round.....

[Jhonno]

You want to run 205/55 and 225/50's if those are the widths you will be using

[JimmyC]

"handling" wont be effected in a huge way by rim diameter and normally this will have just been for looks, however weight and tyre choice will have a huge impact on handling.

So.. Weight and range of tyres availbale should be your key drivers & given that 15" tyres are cheap and easy to come by I'd go for them rather than buy 17" rims and stick crapalto brand tyres on them.

Obviously if you can afford drop forged rims and £1000 a set rubber then your choices are limitless.

As the spudman says, and BBS are a good choice due to being lighter than most aftermarket wheels unless your willing to spend more

[Cotty]

Alpina and Hartge went for 16's and I believe they did that for a good reason rather than just looks..

If that is the case how come I have two sets of 15" Hartge wheels

[Simon13]

Alpina and Hartge went for 16's and I believe they did that for a good reason rather than just looks..

If that is the case how come I have two sets of 15" Hartge wheels

yeah the big brakes they offered on the tuned cars didn't really fit under 15's

[Cotty]

yeah the big brakes they offered on the tuned cars didn't really fit under 15's

So is the 16" not the ideal size as they only increased the size to fit bigger brakes? i.e. a compromise

I have held a Hartge 15" in one hand and a 15" BBS X spoke in the other and I can say that the Hartge is a lot lighter. Even driving with them back to back the Hartge wheels feels lighter, less unsprung weight.