The oversteer/understeer thread got me thinking, rubber on the road?

[hakwuzhere]

So, while I consider myself a decent driver... and Ive been driving BMW 5spd's for 7 of my 13 driving years. I am still wanting to go to a few driving schools to learn how to improve (and take better advantage of my ride!).

The oversteer/understeer thread mentioned alot of things about theory of motion and how the car reacts to different driver innate responses to its actions. Somone also mentioned that the amount of rubber you have on the road has alot to do with how your car handles.

So, to my question. I had been considering purchasing staggered 17x8.5/17x10's for my car... now Im reconsidering that concept due to the fact that I have absolutely no idea how really wide rims will affect the ride in my car. I assume having 10" wides on the rear will improve stability when accellerating off the line (but with no LSD, does this make a difference?) but what will it do to how I drive in the rain/snow?

I really enjoy letting the tail slip a bit on turns in the rain, or even on the occasional dry road.

[Torque]

Narrow tires are preferred for snow as they cut through the snow better. Yes, the wide tires will help traction off the line; but with a 525 ... I don't think you have much to worry about unless you are into some kinky rev to redline then drop the clutch type of starts. lol

[hakwuzhere]

so, then, what is the advantage to 17/10's on a 525? if any?

Other than the absolutely smoking rear lip :)

[Torque]

Pros:
-the wide lip

Cons:
-the outrageous tire price

hah

[hakwuzhere]

Through thewheelexchange I think Im paying $400 for 4 tires with the set of Rondells Im looking at... maybe I should price them out through tirerack aswell since Ill be buying at least two sets a year.

I drive between 30-40k miles a year :(

[stx133]

Putting 10s on the rear will also increace fuel consumption. you would be unlikely to notice the extra traction in a 525

[rob101]

will make you understeer more as well, wow i never knew a thread i started could make people think lol.

Another thing i have heard is that wide tires are more sensitive to chamber change than norrower ones (in terms of grip), which may mean you get more uneven wear, as the 525i suspension wasn't designed for monster tyres although that is not from experience its a reasonable guess from what i know. personally i think the extra grip is not worth the cost or the loss of balance (ie having a more understeering car). sure if you have 300+ hp you might need that extra grip in the rear so you can use the throttle whilst going around a corner, but i don't think in a 525i you need all that extra tyre

[angrypancake]

Jon K has 17x8.5 and 17x10, I think he could help you out. I had that set up on my 535i and it was sweet.

[hakwuzhere]

Jon's also over 400hp now isnt he?... :)

/paging Jon K!

What kind of MPG loss would I see? Right now with city/hwy/fun driving Im getting about 18... EAT chip goes in as soon as it gets here.

[liquidtiger720]

Hmm. well...I have 18x8.5' and 18x9.5's on my e34. The fronts are 235 and the rears are 265 wide. Understeer more? Hell yes. Expensive tires? Hell yes. Increased fuel consumption? maybe .5-1mpg ISH. Look good? well, considering the amount of compliments...I can only conclude they look pretty decent.

[Anthony (M5 in Calgary)]

will make you understeer more as well, wow i never knew a thread i started could make people think lol.

Another thing i have heard is that wide tires are more sensitive to chamber change than norrower ones (in terms of grip), which may mean you get more uneven wear, as the 525i suspension wasn't designed for monster tyres although that is not from experience its a reasonable guess from what i know. personally i think the extra grip is not worth the cost or the loss of balance (ie having a more understeering car). sure if you have 300+ hp you might need that extra grip in the rear so you can use the throttle whilst going around a corner, but i don't think in a 525i you need all that extra tyre

Even with 300+ hp you don't need them. I run 17 x 8.5" on all 4 with 235/45R17Y. Yes, it can be a bit tail happy (but controllable) under high throttle in corners, but is well balanced otherwise. You'd need to be well over 300hp to worry about needing the extra traction and the handling/wear/cost tradeoff is a big factor to consider. That and you cannot rotate tires front to rear which will add to your running cost...

[Marshy]

Well, in the dry, you'll probably never unstick the back end :)

Put it this way: I've got the standard 225 15s on my 540i and I don't want wider rubber. I mean... where's the fun in that? :) :) :)

(Yeah, I know, probably not a totally helpful post. Hey ho, it's Friday night, etc etc.)

(Edit: When I wrote this, there were three posts followed by the quick reply box. Having posted the message, the thread's at over a page already. Colour me confused...)

[hakwuzhere]

(still Paging Jon!)

[Paul in NZ]

235 mm wide is more than a 535 with lsd needs

[rob101]

the 17x8.5's are the m5 throwing star wheels size(see sig picture)? i am confused as i thought my 235s (off e34 in sig picture) were on 8"
I am looking at 16" s for my car (e28 that is) but they all are 8" wide now i wanted to put only 225 and 215 (to counter suicidal e28 oversteer tendencies 225 on the rear of course)on them because my e28 definetely doesn't need 235s, 8" wide rims are the right size to take 225s and 215s? (225 r16/55's that is)


Even with 300+ hp you don't need them. I run 17 x 8.5" on all 4 with 235/45R17Y. Yes, it can be a bit tail happy (but controllable) under high throttle in corners, but is well balanced otherwise. You'd need to be well over 300hp to worry about needing the extra traction and the handling/wear/cost tradeoff is a big factor to consider. That and you cannot rotate tires front to rear which will add to your running cost...

[Anthony (M5 in Calgary)]

the 17x8.5's are the m5 throwing star wheels size(see sig picture)? i am confused as i thought my 235s (off e34 in sig picture) were on 8"
I am looking at 16" s for my car (e28 that is) but they all are 8" wide now i wanted to put only 225 and 215 (to counter suicidal e28 oversteer tendencies 225 on the rear of course)on them because my e28 definetely doesn't need 235s, 8" wide rims are the right size to take 225s and 215s? (225 r16/55's that is)


I use my M-Tech wheels for winter. Summer tires on AC Schnitzer 17 x8.5 ET13:

http://img.photobucket.com/albums/v11/interalian/0e987931.jpg