Pros/Cons of running 245/35/19 and 275/30/19 instead of stock sizes

hoeferland · 10-13-2011, 05:43 PM

Hi all,

I need to replace my stock PS2's with Pilot Super Sports, but Tire Rack is back ordered for 2 months on the stock size rears...so I'm pondering a change to 245/35/19 and 275/30/19's, but am wondering what the pros/cons are of the switch beyond the visual change.

Any help would be greatly appreciated.

gthal · 10-13-2011, 06:02 PM

275/30 rears are too short... you should go 275/35. I ran that and the difference from 265/35 is very small from a visual perspective and gives only a slight improvement in traction.

hoeferland · 10-14-2011, 11:47 AM

Too short? That's what PY Speed recommended. In any case, it seems like you were happy with the change, correct?

llis · 10-14-2011, 12:03 PM

You're one of several people who have posted this question. I suggest some searching.

Also consider different tires. PSSs are nice, but they're not exactly in a class of their own.

alpina527 · 10-14-2011, 12:39 PM

275s will give slightly more drag, but won't give any more traction. Best to wait for the 265s to come in unless you want the visual.

persian54 · 10-14-2011, 12:57 PM

245/35 275/35 will be better than 275/30

if you must do a 30 series profile, do a 285/30

elh0102 · 10-15-2011, 07:40 AM

The potential issue I see, the rear would be a slightly smaller OD than the front. Since DSC is programmed with a larger rear OD, the wheel rpm is going to be indicating wheel spin (in error) much earlier, so if you use DSC, you may see it activate prematurely. I use a set of 275/35-18, and I can detect a small difference in DSC activity with equal sizes all around. I use them mostly on track with DSC off, so it's not an issue. I suggest using the 255/35 and 275/35 combination on your OE 19" wheels.

gthal · 10-15-2011, 01:53 PM

Quote:

Originally Posted by llis

You're one of several people who have posted this question. I suggest some searching.

Also consider different tires. PSSs are nice, but they're not exactly in a class of their own.

IMO, the PSS is pretty much in a class of its own as a street performance tire as it gets everything right (right, quiet, responsiveness, grip, wet). If you are using the tires on the track, then I agree that the RE-11 and AD-08 are better.

LarThaL · 10-15-2011, 07:38 PM

Quote:

Originally Posted by hoeferland

Too short? That's what PY Speed recommended. In any case, it seems like you were happy with the change, correct?

275/30 is too short. Do the math yourself. 265/35 has a 14mm greater rolling diameter than 245/35. 275/30 has a 20mm lower rolling diameter than the stock 265/35 so it is actually smaller than the fronts.

You could go:

255/35 and 275/35

255/35 and 295/30 (This will give you equal F/R rolling diameter)

245/35 and 285/30 (This will give you equal F/R rolling diameter)

hoeferland · 10-16-2011, 08:40 AM

Great feedback everyone. Yes, I've searches across the threads, but wasn't finding the feedback I was hoping for. This all helps and $ aside I do feel the PS2s and PSS are the best tires for mixed use (primarily street with occasional hot laps at the track).

10-13-2011, 05:43 PM	#1
hoeferland Private First Class Drives: 2008 E90 M3 Sedan Join Date: Jan 2010 Location: Portland, Oregon Posts: 140 iTrader: (2)	Pros/Cons of running 245/35/19 and 275/30/19 instead of stock sizes Hi all, I need to replace my stock PS2's with Pilot Super Sports, but Tire Rack is back ordered for 2 months on the stock size rears...so I'm pondering a change to 245/35/19 and 275/30/19's, but am wondering what the pros/cons are of the switch beyond the visual change. Any help would be greatly appreciated.
	Tweet

10-13-2011, 06:02 PM	#2
gthal Colonel Drives: C63 coupe Join Date: Jul 2007 Location: Canada Posts: 2,054 iTrader: (2) Garage List 2011 M3 [3.37]	275/30 rears are too short... you should go 275/35. I ran that and the difference from 265/35 is very small from a visual perspective and gives only a slight improvement in traction. __________________ 2014 Corvette Stingray \| Cyber Grey \| Z51 \| On order... 2012 C63 coupe \| Obsidian Black \| Performance Package (481hp, 443ft/lbs) \| Sold 2011 M3 coupe \| Jerez Black \| ZCP/DCT \| Sold but never forgotten nor will the love affair end 2010 M3 coupe \| Alpine White \| 6MT \| Sold

10-14-2011, 12:03 PM	#4
llis snarkarina Drives: M3s Join Date: Oct 2010 Location: Colorado Posts: 1,017 iTrader: (0) Garage List 2013 BMW M3 [5.00] 1998 BMW M3 (GTS-2) [0.00] 2002 530i [0.00]	You're one of several people who have posted this question. I suggest some searching. Also consider different tires. PSSs are nice, but they're not exactly in a class of their own. __________________ 2013 E92 ///M3 ZCP 6MT » 1998 E36 ///M3 [GTS-2] Toot Sweet Racing

10-14-2011, 12:57 PM	#6
persian54 Lieutenant General Drives: MW E93 M3/E89 Z4 35i Join Date: Jun 2009 Location: The Valley, SoCal Posts: 15,401 iTrader: (260)	245/35 275/35 will be better than 275/30 if you must do a 30 series profile, do a 285/30 __________________ Next track day: http://www.m3post.com/forums/showthread.php?t=651089 Sorry I'm just someone who comes on here to fill a void..I dont have the $ to own a BMW. This is a nice E93:http://www.e90post.com/forums/showthread.php?t=434032

10-15-2011, 07:40 AM	#7
elh0102 Captain Drives: E92 M3 Join Date: Apr 2010 Location: USA Posts: 704 iTrader: (0)	The potential issue I see, the rear would be a slightly smaller OD than the front. Since DSC is programmed with a larger rear OD, the wheel rpm is going to be indicating wheel spin (in error) much earlier, so if you use DSC, you may see it activate prematurely. I use a set of 275/35-18, and I can detect a small difference in DSC activity with equal sizes all around. I use them mostly on track with DSC off, so it's not an issue. I suggest using the 255/35 and 275/35 combination on your OE 19" wheels. __________________ 2011 Space Gray Coupe, DCT, ZCP, StopTech ST-60/ST-40 BBK.

10-14-2011, 11:47 AM	#3
hoeferland Private First Class Drives: 2008 E90 M3 Sedan Join Date: Jan 2010 Location: Portland, Oregon Posts: 140 iTrader: (2)	Too short? That's what PY Speed recommended. In any case, it seems like you were happy with the change, correct?

10-14-2011, 12:39 PM	#5
alpina527 Captain Drives: 2008 E92 M3 DCT JZB/FR Join Date: Jan 2010 Location: London, England Posts: 629 iTrader: (1)	275s will give slightly more drag, but won't give any more traction. Best to wait for the 265s to come in unless you want the visual.

10-16-2011, 08:40 AM	#10
hoeferland Private First Class Drives: 2008 E90 M3 Sedan Join Date: Jan 2010 Location: Portland, Oregon Posts: 140 iTrader: (2)	Great feedback everyone. Yes, I've searches across the threads, but wasn't finding the feedback I was hoping for. This all helps and $ aside I do feel the PS2s and PSS are the best tires for mixed use (primarily street with occasional hot laps at the track). __________________ Hoeferland \| 2008 E90 M3 \| Alpine White \| 6MT \| 20" HRE P40s \| Full Active Autowerke Cat-less Signature System \| BPMSport Tune \| Eibach Springs & E36 Bumps \| Active Autowerke Underdrive Pulley

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search