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[m3gtrdtm]

Have had this idea in my mind for awhile. Discuss...

A photochop would be welcome.

[ulrichd]

I once mentioned this on a BMW board when I had my 00 M-Coupe, and someone much smarter than me, replied using terms like "rotational mass difference". I dropped it

[SpeedballTrix]

"Bigs and littles" is for drag cars.
The idea is more rubber in the rear (a larger rolling diameter at the same tire pressure will create a larger contact patch) for straight line grip and smaller lighter wheels in the front, plus pitching the car forward adds downforce.
However, for track racing you are much better off keeping the same rolling diameter on all four corners and playing with the tire widths (and suspension) to add traction where you need it and remove weight.

[esses]

You can't bling in limp mode.

[rcracer_tx]

I would imagine this would screw with your stability control big time, not worth it IMHO.

[Caduceus]

Can't see it working on your BMW but Lotus have great success with it on most of their cars. They know a thing or two about performance.....

[FazerBoy]

Most of the replies seem to be negative based on the fact that they are assuming that the overall diameters of the front and rear wheels would be different. However, if lower profile rubber was mounted at the rear than up front then the overall diameters could be kept the same.

On the other hand what would be the point of doing this?



Jack

[boostin]

Originally Posted by FazerBoy

Most of the replies seem to be negative based on the fact that they are assuming that the overall diameters of the front and rear wheels would be different. However, if lower profile rubber was mounted at the rear than up front then the overall diameters could be kept the same.

On the other hand what would be the point of doing this?



Jack

i was under the impression that as long as the overall diameter of the wheel/tire setup is the same, then you're good. so for instance, if you wanted to use the stock front tire setup (215/40/18) then you would need a 245/30/19 tire setup in the rear to have the same diameter. the C5 ZO6 has 17's in the front and 18's in the back.

[FazerBoy]

Yeah, Boostin, that's exactly what I meant. That setup would work fine and not mess up the electronics etc. However, why would one want to do this as opposed to simply running 18s with 215/40/18 and 245/35/18? would it be for the looks?

Jack

[fourtailpipes]

correct. if total diameter is within +/- 5% or so, the car won't know the difference. personally i think this will look ridiculous, but if you want to try it, try it. many road race cars do the opposite (smaller diameter rear wheels) because they need to accomodate larger front brakes.

[boostin]

Originally Posted by FazerBoy

Yeah, Boostin, that's exactly what I meant. That setup would work fine and not mess up the electronics etc. However, why would one want to do this as opposed to simply running 18s with 215/40/18 and 245/35/18? would it be for the looks?

Jack

yeah, its for looks. i would consider doing 18s in the front and 19s in the back because USUALLY (on the 135i) if you're running a wheel with a lip (spokes don't go to the edge of the wheel) 18s look a little small, so i would do those in the front and 19s in the back. but, if you're running a wheel where the spokes go to the edge of the wheel (M6 wheel, CSL wheel) then you can get away with 18s on the 135i

[fourtailpipes]

Originally Posted by boostin

yeah, its for looks. i would consider doing 18s in the front and 19s in the back because USUALLY (on the 135i) if you're running a wheel with a lip (spokes don't go to the edge of the wheel) 18s look a little small, so i would do those in the front and 19s in the back. but, if you're running a wheel where the spokes go to the edge of the wheel (M6 wheel, CSL wheel) then you can get away with 18s on the 135i

your logic eludes me... but try it and post pics!

[Motorsports_3]

That is a horrible idea. Dont do it. Just run 18's all around

[boostin]

Originally Posted by fourtailpipes

your logic eludes me... but try it and post pics!

you must be new to performance cars - vettes have done different size wheels front and back for years now...

some people even run 18's in the front and 17's in the back because its much easier to find a drag radial in a 17" fashion than an 18"

as for rim style, you can't understand that an 18" wheel with a lip can look undersized on certain cars? the lip makes the "face" of the wheel smaller. however, when the spokes go all the way to the end of the wheel (no lip) the wheel looks larger. i don't know how else to explain it.

[arok]

I was considering it, but we don't have many options right now to do the 18/19 combo... it wouldn't really matter except you'll be buying two different tire sizes.. but should look cool. 18's in the rear looks a tad small, but 19's in the front is too big lol

[rcracer_tx]

Originally Posted by arok

I was considering it, but we don't have many options right now to do the 18/19 combo... it wouldn't really matter except you'll be buying two different tire sizes.. but should look cool. 18's in the rear looks a tad small, but 19's in the front is too big lol

Usually on a staggered setup like that you keep around the same profile tires as if they were the same size wheel, but either the front tire has a smaller diameter with similar sidewall size as the rear, or the back has tire that is a larger in diameter than stock...

[boostin]

Originally Posted by arok

18's in the rear looks a tad small, but 19's in the front is too big lol

exactly! that's why i decided on 19's all-around. i'd rather have it look a little too big in the front than too small in the rear.

[fmxomar]

Originally Posted by Motorsports_3

That is a horrible idea. Dont do it. Just run 18's all around

haha seriously there is absolutely no point in this..

p.s. 19s ftl

[boostin]

Originally Posted by fmxomar

haha seriously there is absolutely no point in this..

p.s. 19s ftl

18s FTL - cute little baby wheels

[arok]

Originally Posted by rcracer_tx

Usually on a staggered setup like that you keep around the same profile tires as if they were the same size wheel, but either the front tire has a smaller diameter with similar sidewall size as the rear, or the back has tire that is a larger in diameter than stock...

i was talking pure aesthetics... but yes, rolling diameters should be within a +/- 3-5% or else you'll have issues as mentioned above

[fourtailpipes]

Originally Posted by boostin

you must be new to performance cars - vettes have done different size wheels front and back for years now...

some people even run 18's in the front and 17's in the back because its much easier to find a drag radial in a 17" fashion than an 18"

as for rim style, you can't understand that an 18" wheel with a lip can look undersized on certain cars? the lip makes the "face" of the wheel smaller. however, when the spokes go all the way to the end of the wheel (no lip) the wheel looks larger. i don't know how else to explain it.

refer to my above post, #10.

you try to rag on me by parroting what i said above? weak.

and yes, i understand what you're saying about wheels with a lip looking smaller. i don't see how you get from that fact to concluding that bigger diameter rears would look better. how is that even relevant? are you going to have a wheel with a tall lip in the back, but not the front? if you think an 18" wheel with a lip looks too small, wouldn't you just want 19" with a lip front AND rear?

so like i said... your logic doesn't make sense to me, but more importantly, that doesn't matter. try it... maybe it'll look great.

[boostin]

Originally Posted by fourtailpipes

refer to my above post, #10.

you try to rag on me by parroting what i said above? weak.

and yes, i understand what you're saying about wheels with a lip looking smaller. i don't see how you get from that fact to concluding that bigger diameter rears would look better. how is that even relevant? are you going to have a wheel with a tall lip in the back, but not the front? if you think an 18" wheel with a lip looks too small, wouldn't you just want 19" with a lip front AND rear?

so like i said... your logic doesn't make sense to me, but more importantly, that doesn't matter. try it... maybe it'll look great.

you said people run a larger wheel in the front to accommodate larger brakes. i didn't parrot what you said since i was talking about a smaller wheel in the rear due to more variety for drag radials; different statement.

why did i say 19s with a lip look better in the rear, and how is it relevant? somebody mentioned above that 18s in the rear look too small on a 1-series. i agreed and so do some other people in this thread. some people think that 18s are too small for the rear, and 19s are a tad too big for the front; hence why some would want a 18 for the front and 19 for the rear.

however, my original statement was that you can definitely pull off 18's on a 1-series IF the spokes go out to the edge of the rim (no lip). IMO, if you want a wheel for your 1-series that has a LIP, then get 19's. thats all...