305/30-19 square
#1
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Thread Starter
305/30-19 square
Gents,
Issue with 2017 GS running 305/30-19 RE-71 R-square: The traction control is VERY HEAVY handed for the first quarter mile or so with the traction control/active management engaged, and then seemingly it 'learns' and everything is ok. I run with everything shut off 99.999% of the time, however there have been two occasions running in the RAIN in which(2014 Z51) that I was on Charlotte at speed on the banking and infield, and on a long autocross event bumping the rev limiter in 2nd multiple times in which I used track/sport 1. Obviously this is a problem in an autocrossing format, if I to want to use the very limited PTM in Track/Sport 1, and can't drive around before staging.
PROBLEM/SOLUTION: Is there a way to get around this, and/or has anyone had similar experiences and what did you do???
With respect, I'd appreciate knowledgeable answers only, Ok
I am autocrossing mostly, and will track occasionally.
sincerely
Bruce
Issue with 2017 GS running 305/30-19 RE-71 R-square: The traction control is VERY HEAVY handed for the first quarter mile or so with the traction control/active management engaged, and then seemingly it 'learns' and everything is ok. I run with everything shut off 99.999% of the time, however there have been two occasions running in the RAIN in which(2014 Z51) that I was on Charlotte at speed on the banking and infield, and on a long autocross event bumping the rev limiter in 2nd multiple times in which I used track/sport 1. Obviously this is a problem in an autocrossing format, if I to want to use the very limited PTM in Track/Sport 1, and can't drive around before staging.
PROBLEM/SOLUTION: Is there a way to get around this, and/or has anyone had similar experiences and what did you do???
With respect, I'd appreciate knowledgeable answers only, Ok
I am autocrossing mostly, and will track occasionally.
sincerely
Bruce
#2
You need to keep the ratio between front and rear tire. If you run the same height front and rear, you will have issues. I know of no way around it.
Last edited by rb185afm; 04-24-2018 at 11:58 AM.
#3
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Thread Starter
As I said, I have everything off, so I'll just leave it that way!
Last edited by Bruce0293; 04-24-2018 at 11:51 AM.
#4
Le Mans Master
I'm not sure if you have class rules but I run the R888R with 315F and 335R on 18" wheels.
With that said, OEM Cup2 are undoubtedly faster, despite being heavier on a bigger and heavier cast wheel with a skinnier front tire. R888R heats up faster though.
With that said, OEM Cup2 are undoubtedly faster, despite being heavier on a bigger and heavier cast wheel with a skinnier front tire. R888R heats up faster though.
Last edited by village idiot; 04-24-2018 at 12:58 PM.
#5
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Thread Starter
Unfortunately.... another kink, is in street class(basically no modifications/very limited mods) you have to run a tire with 200 tread wear or greater.... sigh :-)
#6
Le Mans Master
#7
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Thread Starter
#8
Le Mans Master
Crap, well, in that case I have nothing to add here and apologize for wasting internets.
#9
Advanced
Gents,
Issue with 2017 GS running 305/30-19 RE-71 R-square: The traction control is VERY HEAVY handed for the first quarter mile or so with the traction control/active management engaged, and then seemingly it 'learns' and everything is ok. I run with everything shut off 99.999% of the time, however there have been two occasions running in the RAIN in which(2014 Z51) that I was on Charlotte at speed on the banking and infield, and on a long autocross event bumping the rev limiter in 2nd multiple times in which I used track/sport 1. Obviously this is a problem in an autocrossing format, if I to want to use the very limited PTM in Track/Sport 1, and can't drive around before staging.
PROBLEM/SOLUTION: Is there a way to get around this, and/or has anyone had similar experiences and what did you do???
With respect, I'd appreciate knowledgeable answers only, Ok
I am autocrossing mostly, and will track occasionally.
sincerely
Bruce
Issue with 2017 GS running 305/30-19 RE-71 R-square: The traction control is VERY HEAVY handed for the first quarter mile or so with the traction control/active management engaged, and then seemingly it 'learns' and everything is ok. I run with everything shut off 99.999% of the time, however there have been two occasions running in the RAIN in which(2014 Z51) that I was on Charlotte at speed on the banking and infield, and on a long autocross event bumping the rev limiter in 2nd multiple times in which I used track/sport 1. Obviously this is a problem in an autocrossing format, if I to want to use the very limited PTM in Track/Sport 1, and can't drive around before staging.
PROBLEM/SOLUTION: Is there a way to get around this, and/or has anyone had similar experiences and what did you do???
With respect, I'd appreciate knowledgeable answers only, Ok
I am autocrossing mostly, and will track occasionally.
sincerely
Bruce
I’ve run 305/19 square RE-71s for a year and a half now. Occasionally I’ll have TC issues when I first swap from my stock 19/20 wheels to my 19/19 autocross setup. It takes a few miles on the road to get the tire pressure sensors talking to the car correctly. I’ll inflate my 19/19 wheels to 36psi or so and watch the pressures on the dash, once they change from 30ish to 36psi I know I’m good. Once the sensors are talking correctly, I have had no issues in any PTM mode on track, autocross, or street driving with the 305/19 setup.
#11
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Thread Starter
I’ve run 305/19 square RE-71s for a year and a half now. Occasionally I’ll have TC issues when I first swap from my stock 19/20 wheels to my 19/19 autocross setup. It takes a few miles on the road to get the tire pressure sensors talking to the car correctly. I’ll inflate my 19/19 wheels to 36psi or so and watch the pressures on the dash, once they change from 30ish to 36psi I know I’m good. Once the sensors are talking correctly, I have had no issues in any PTM mode on track, autocross, or street driving with the 305/19 setup.
When autocrossing and once at the event, the car will sit for an extended time prior to first run, and the is no good way to drive it around?
Do the sensors have to re-learn every time it is started with the square set up?
#12
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Thread Starter
SCCA rules state that the offsets can move outward by + 5mm for class rules, and you need to run factory 10" widths. However factory widths and offsets will work fine. My first autox will be this weekend, but 5 miles of street show no signs of any rubbing. (just got them mounted on car and have had no time to drive it)
#14
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I'm using replica wheels 19x10 +40 front and 19x12 +59 rear. No major rubbing, they do rub a little on the inner fender liner at the top of the wheel where it meets the fender.
#15
Melting Slicks
Member Since: Feb 2009
Location: Dallas Georgia
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2020 Corvette of the Year Finalist (track prepared)
C3 of Year Winner (track prepared) 2019
For Autocross!? Both of those are pretty terrible choices for that kind of event. If he were doing track days, I would agree with you.
#16
Le Mans Master