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View Full Version : Why does the E46 M3 have a 225 front tire?


Moderato
04-25-2005, 04:18 PM
I'm just wondering why the width of the front tire of the e46 M3 is 225, which is the same as my 330i SP front tire of 225?

bren
04-25-2005, 04:54 PM
I'll take a few guesses:

Lots of understeer so less people kill themselves

To keep the steering light

Minimize tramlining

BahnBaum
04-25-2005, 06:11 PM
In addition to what Bren mentioned, saving a few bucks prolly doesn't hurt.

Alex

Pinecone
04-26-2005, 02:24 AM
Plus looks cool.

But since the cars weight the same, there is no reason to change the front tire sie. The rears are slightly wider to deal with the extra power coming out of turns.

Moderato
04-26-2005, 06:35 AM
So regarding cornering and understeering would the 330i SP feel similar to the M3 in terms of tire grip? I know the M3 has a stiffer suspension, sways etc...but I've also read that cornering grip depends on the contact patch of the tire and a car that rolls a bit in a turn can have more grip then one which stays flat, depending. :dunno: I guess what I'm getting at, is how can the M3 be much faster through a tight turn then the 330i SP since both cars have about the same width tires? Because even though the 330i SP doesn't have as aggressive of a setup as the M3, it doesn't have a Buick suspension either.

Nick325xiT 5spd
04-26-2005, 06:38 AM
So regarding cornering and understeering would the 330i SP feel similar to the M3 in terms of tire grip? I know the M3 has a stiffer suspension, sways etc...but I've also read that cornering grip depends on the contact patch of the tire and a car that rolls a bit in a turn can have more grip then one which stays flat, depending. :dunno: I guess what I'm getting at, is how can the M3 be much faster through a tight turn then the 330i SP since both cars have about the same width tires? Because even though the 330i SP doesn't have as aggressive of a setup as the M3, it doesn't have a Buick suspension either.
The 330 and 325 should be faster through very tight turns. They weigh a lot less. The M3 just makes it up once you get on the gas.

TeamM3
04-26-2005, 07:01 AM
I'll take a few guesses:

Lots of understeer so less people kill themselves

To keep the steering light

Minimize tramlining


you forgot one:

BMW engineers are idiots :dunno:

otherwise all of the above would make sense if it was a Chevy Cavalier :tsk:

Moderato
04-26-2005, 07:19 AM
I'll take a few guesses:

Lots of understeer so less people kill themselves

To keep the steering light

Minimize tramliningyou forgot one:

BMW engineers are idiots :dunno:

otherwise all of the above would make sense if it was a Chevy Cavalier :tsk:

Sorry TeamM3, but all this went over my head. Are you joking, serious, being sarcastic? :confused:

Pinecone
04-26-2005, 03:53 PM
So regarding cornering and understeering would the 330i SP feel similar to the M3 in terms of tire grip? I know the M3 has a stiffer suspension, sways etc...but I've also read that cornering grip depends on the contact patch of the tire and a car that rolls a bit in a turn can have more grip then one which stays flat, depending. :dunno: I guess what I'm getting at, is how can the M3 be much faster through a tight turn then the 330i SP since both cars have about the same width tires? Because even though the 330i SP doesn't have as aggressive of a setup as the M3, it doesn't have a Buick suspension either.

Strut front suspensions work best with less body roll. Stiffer sways, stiffer springs give less body roll, so better handling. Lower center of gravity means better handling, M3 is lower, with lower CoG, so better handling. Better dampening shocks, means better handling, in most cases, M3 has more dampening.

Different tires, better tires on the 330 will help.

And lastly, it is about corner exit speed, and power does help here.

And yes, BMW engineers are idiots, except look at the number of E46 M3 drivers that have wrapped their cars up even with massive understeer built in. That's why several of us are going to square tire setups (265s all around) with as much negative camber we can get in the front. Adding in a stiff front bar and aftermarket shocks.

bren
04-26-2005, 06:06 PM
Sorry TeamM3, but all this went over my head. Are you joking, serious, being sarcastic? :confused:
He means there is no resonable excuse for BMW to put such tiny tires on the M3....and I'm sure he would also mention that the wheels are also entirely too narrow.

Pinecone
04-27-2005, 02:45 AM
Yes there is a reason, liability.