235/265 Direzza ZII vs 245 Square RE-11A?

Stohlen · 08-16-2013, 09:50 AM

Quote:

Originally Posted by Kgolf31

Quote:

Originally Posted by Stohlen

Both manufacturers do it for traction, not looks... Thats the whole point. Turn the car with the throttle.

Easier said than done.

Rear Engine, RWD vs Front Engine RWD.

Lets not forget that you don't have an LSD, so good luck trying to rotate the rear with the 1 wheel drive.

Quote:

Originally Posted by blutattoo

You could run 255/35/18 R-S3's square. I run 255's up front w/2 deg neg camber on apex arc-8s without rubbing. Just a thought if you want the biggest contact patch. I ran the RE-11's prior to that and they were great at first. Really fell off after 8-10 track days, but they lasted longer than I expected so I'm guessing the RE-11a's are even better.

Good information. Glad you can run 255s w/out rolling the lip

I do have one. But the elsd in most people's vehicles helps a little. Again not as many traction issues with more tire. Helps you add more throttle and turn the car

Pyrat 2 · 08-18-2013, 09:38 AM

You can't apply the square is better equally to all cars. The 1 like all BMWs has a close to 50/50 weight distribution. For this case a square setup should give the most balanced scenario with zero under steer or oversteer. Suspension certainly factors into this but in general the square setup will give less under steer than the staggered setup.

For a Porsche 911 class car a square setup is not ideal simply because of the weight distribution of the car. It is not 50/50. I think it's about 60% in back but don't quote me.

Interesting article on weight distribution here:

http://www.caranddriver.com/features...11-gt3-feature

nate340 · 08-30-2013, 02:23 AM

you're saying that a wider rear tire in a staggered setup will allow you to get on the power earlier on corner exit. but when you pick up the throttle earlier from the apex you accelerate hard the weight transfers off the front tires and you start pushing wide to such an extreme you have to lift off or risk going off track. ask me how i know and I'm running a square 225 setup on either ZII's or R1's even slow speed corners rear end grip is never the issue as the front end loses grip first under almost all circumstances. Running a square setup helps rotate the car on throttle instead of relying on the front tires to steer the car from apex out.

Nugget · 08-30-2013, 02:52 AM

Quote:

Originally Posted by nate340

you're saying that a wider rear tire in a staggered setup will allow you to get on the power earlier on corner exit. but when you pick up the throttle earlier from the apex you accelerate hard the weight transfers off the front tires and you start pushing wide to such an extreme you have to lift off or risk going off track. ask me how i know and I'm running a square 225 setup on either ZII's or R1's even slow speed corners rear end grip is never the issue as the front end loses grip first under almost all circumstances. Running a square setup helps rotate the car on throttle instead of relying on the front tires to steer the car from apex out.

That's not how my car behaves unless I am exceptionally ham fisted. But I have camber plates, coilovers, M3 control arms and bushings.

nate340 · 08-30-2013, 10:32 PM

I'm quite jealous I''ll admit that my car is completely stock other than the tires and a Cobb AP running stage 1 aggressive. I'm happily surprised that the cars attitude can be so significantly altered with a few simple mods. right now my car loves to understeer the only way i can get the back end to lose grip and rotate is if i treat the throttle pedal as an off and on switch. when you say bushings are you talking about the rear subframe bushings?

08-18-2013, 09:38 AM	#24
Pyrat 2 Colonel 1418 Rep 2,560 Posts Drives: Rapidly from A to B Join Date: Jun 2005 Location: Chicago 'burbs or TN Smokies iTrader: (3) Garage List 2022 Porsche GT4 [9.64] 2018 Porsche GT3 [9.33] 2007 Z4 M Roadster [8.33] 2020 BMW X1 [0.00]	You can't apply the square is better equally to all cars. The 1 like all BMWs has a close to 50/50 weight distribution. For this case a square setup should give the most balanced scenario with zero under steer or oversteer. Suspension certainly factors into this but in general the square setup will give less under steer than the staggered setup. For a Porsche 911 class car a square setup is not ideal simply because of the weight distribution of the car. It is not 50/50. I think it's about 60% in back but don't quote me. Interesting article on weight distribution here: http://www.caranddriver.com/features...11-gt3-feature __________________ '07 Z4MR '22 GT4 '18 GT3 '16 GT4, '16 M2, '14 X1, '13 135is, '06 330i, '03 323 Ci, '01 330i, '99 M3 (RIP), '96 318is, some non-BMWs
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08-30-2013, 02:23 AM	#25
nate340 Enlisted Member 6 Rep 40 Posts Drives: 135i Join Date: Apr 2013 Location: Canada iTrader: (0)	you're saying that a wider rear tire in a staggered setup will allow you to get on the power earlier on corner exit. but when you pick up the throttle earlier from the apex you accelerate hard the weight transfers off the front tires and you start pushing wide to such an extreme you have to lift off or risk going off track. ask me how i know and I'm running a square 225 setup on either ZII's or R1's even slow speed corners rear end grip is never the issue as the front end loses grip first under almost all circumstances. Running a square setup helps rotate the car on throttle instead of relying on the front tires to steer the car from apex out.
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08-30-2013, 10:32 PM	#27
nate340 Enlisted Member 6 Rep 40 Posts Drives: 135i Join Date: Apr 2013 Location: Canada iTrader: (0)	I'm quite jealous I''ll admit that my car is completely stock other than the tires and a Cobb AP running stage 1 aggressive. I'm happily surprised that the cars attitude can be so significantly altered with a few simple mods. right now my car loves to understeer the only way i can get the back end to lose grip and rotate is if i treat the throttle pedal as an off and on switch. when you say bushings are you talking about the rear subframe bushings?
	Appreciate 0 Quote