understearing now?! - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

caper · 06-18-2011, 10:06 PM

first time i felt the stability control really come on in a turn. wasnt go way fast, nothing i didnt do before on stock tires without an issue, but now with 275 on front and 315 rear, it seems to push enough for the nannys to kick in enough to feel it. shouldnt be doing better not worse in the cornering dept?? the 275 and p zero rosso, so they should be as goos as the originals. the 315 are sportmax run flats.

btw this is a long sweeping turn with slight throttle input, not on the brakes. it is downhill but like i said, i dont feel like i am going THAT fast or anywhere near the edge of grip ... car doesnt give any signs of traction issues up to that point.

My 5th · 06-18-2011, 10:34 PM

Wider rear wheels and tires reduce OVERsteer, hence INCREASE UNDERsteer--without any other compensating adjustments. You will need different swaybars now to approach a more neutral cornering attitude.

I have 9.5" wheels up front with 275/40's and 11" wheels in back with 315's, but I have the Pedders Xa's and Solution B swaybars. I feel my car has just a touch of understeer now, which I can convert to neutral/oversteer with a little throttle.

I went through some tight twisty mountain roads recently at over 50 MPH, the curves were posted for 25 mph. I don't recall my tires even squealing through those turns.

Jay_LHD3 · 06-18-2011, 10:54 PM

Probably doesn't help that you're running different rubber compound front and back.

I'm running 265s up front and 315s out back with no noticable difference in nanny control... and I like to get on it when going through the twisties!!

Rudy@Tirerack · 06-22-2011, 05:55 PM

I agree that is not a good mix your running. Runflats have a much stiffer side wall than a standard tire. This is probably leading to the handling issues and not the sizes.

caper · 06-22-2011, 08:01 PM

Yea, something isn't right, stabilitrac kicks in way to early. With it off I take turns with no issue at all. Same speed with it on, crappy. Like someone throws an anchor out,

DietCoke · 06-22-2011, 08:05 PM

Runflats suck

clg_98ta · 06-23-2011, 07:19 AM

Quote:

Originally Posted by Rudy@Tirerack

I agree that is not a good mix your running. Runflats have a much stiffer side wall than a standard tire. This is probably leading to the handling issues and not the sizes.

+1

caper · 06-23-2011, 04:04 PM

i dont think its the sizes, but something is messing up the stabilitrack...like i said when i take these turns without it on, i get no slide, no push etc...but with it on, its as if the car cuts out. i dont have a lot of faith in it now...BTW i have charged some pretty hard turns before, and it never cut in. i cant really push it to see where the limit of grip is on the street but i know i am not at it when the stabilirack is cutting in. if you were in my car you would think there was something wrong with it.

06-18-2011, 10:06 PM	#1
caper Drives: 2010 IOM 2ss/RS Join Date: Sep 2009 Location: SoCal, I.E. Posts: 1,545	understearing now?! first time i felt the stability control really come on in a turn. wasnt go way fast, nothing i didnt do before on stock tires without an issue, but now with 275 on front and 315 rear, it seems to push enough for the nannys to kick in enough to feel it. shouldnt be doing better not worse in the cornering dept?? the 275 and p zero rosso, so they should be as goos as the originals. the 315 are sportmax run flats. btw this is a long sweeping turn with slight throttle input, not on the brakes. it is downhill but like i said, i dont feel like i am going THAT fast or anywhere near the edge of grip ... car doesnt give any signs of traction issues up to that point.

06-18-2011, 10:34 PM	#2
My 5th Drives: 2010 2SS/RS M6 Black on Black Join Date: Jan 2010 Location: Global Citizen Posts: 1,243	Wider rear wheels and tires reduce OVERsteer, hence INCREASE UNDERsteer--without any other compensating adjustments. You will need different swaybars now to approach a more neutral cornering attitude. I have 9.5" wheels up front with 275/40's and 11" wheels in back with 315's, but I have the Pedders Xa's and Solution B swaybars. I feel my car has just a touch of understeer now, which I can convert to neutral/oversteer with a little throttle. I went through some tight twisty mountain roads recently at over 50 MPH, the curves were posted for 25 mph. I don't recall my tires even squealing through those turns. __________________ Meh

06-22-2011, 08:05 PM	#6
DietCoke Slow Turtle Drives: 2011 1SS Join Date: Jun 2011 Location: Manhattan, KS Posts: 1,123	Runflats suck __________________ LSXOCET - 404rwhp @ 1600 lbs curb weight... bonkers fast https://www.facebook.com/lsxocet

06-18-2011, 10:54 PM	#3
Jay_LHD3 Drives: 2019 F150 RCSB Abyss FX4 Join Date: Aug 2009 Location: Huntsville, AL Posts: 2,277	Probably doesn't help that you're running different rubber compound front and back. I'm running 265s up front and 315s out back with no noticable difference in nanny control... and I like to get on it when going through the twisties!!

06-22-2011, 05:55 PM	#4
Rudy@Tirerack Drives: 1-800-428-8355 X4664 Join Date: Sep 2010 Location: rudy@tirerack.com Posts: 1,186	I agree that is not a good mix your running. Runflats have a much stiffer side wall than a standard tire. This is probably leading to the handling issues and not the sizes.

06-22-2011, 08:01 PM	#5
caper Drives: 2010 IOM 2ss/RS Join Date: Sep 2009 Location: SoCal, I.E. Posts: 1,545	Yea, something isn't right, stabilitrac kicks in way to early. With it off I take turns with no issue at all. Same speed with it on, crappy. Like someone throws an anchor out,

06-23-2011, 04:04 PM	#8
caper Drives: 2010 IOM 2ss/RS Join Date: Sep 2009 Location: SoCal, I.E. Posts: 1,545	i dont think its the sizes, but something is messing up the stabilitrack...like i said when i take these turns without it on, i get no slide, no push etc...but with it on, its as if the car cuts out. i dont have a lot of faith in it now...BTW i have charged some pretty hard turns before, and it never cut in. i cant really push it to see where the limit of grip is on the street but i know i am not at it when the stabilirack is cutting in. if you were in my car you would think there was something wrong with it.