[ICTsccaCamaro]

The car is a complete animal on the 355's ACR's you can be abusive with the throttle coming out of corners, you will need to run a lot of rear camber so the tire can just barely tuck in to the rear fender lip under full compression. (and of course move the rear harness)
I am running around -2.2ﾟ in the rear and have put a little bit of track wrap (clear film) on the edge of the fender because there is still some slight rubbing under extremely hard compression while on track, I can not comment on the street driving side of things as mine is purely just a trailer queen for track and auto cross

[TheRealJA105]

Originally Posted by 2018$S1le

Yeah I noticed the 305/30-19 didn’t have the ACR designation so I did some digging and found what you said. These are just street tires for me though. I plan to get a 2nd set of wheels and remount the GY’s.

Good plan

Originally Posted by ICTsccaCamaro

The car is a complete animal on the 355's ACR's you can be abusive with the throttle coming out of corners, you will need to run a lot of rear camber so the tire can just barely tuck in to the rear fender lip under full compression. (and of course move the rear harness)
I am running around -2.2ﾟ in the rear and have put a little bit of track wrap (clear film) on the edge of the fender because there is still some slight rubbing under extremely hard compression while on track, I can not comment on the street driving side of things as mine is purely just a trailer queen for track and auto cross

Awesome! What front tires do you run again? 305 RE-71s?

[ICTsccaCamaro]

Originally Posted by TheRealJA105

Good plan


Awesome! What front tires do you run again? 305 RE-71s?

Yeah 305 re71r's

[TheRealJA105]

Originally Posted by ICTsccaCamaro

Yeah 305 re71r's

Good enough to not make it understeer with the 355s bulldozing their way forward out back?

[ICTsccaCamaro]

Originally Posted by TheRealJA105

Good enough to not make it understeer with the 355s bulldozing their way forward out back?

I've got the rear sway bar set on the soft setting and the 305/355 tire combo, but if you are stupid with the throttle mid corner the back end will step out and oversteer, this is one car that I have never had a understeer issue with.

[SFV1LE]

Originally Posted by Jason18ZL1LE

I recall you saying that the 345s were equal to the width of the 325 SC3R.. what was your overall opinion on the PSC2 in 345 vs the SC3R in 325s? I was there the same day as you but with the factory sizing PSC2 and sliding all over the place. Hated the PSC2 with my power levels in the factory sizing

Hi Jason, yeah I remember you at ACS--you broke a canard right? The GY SC3R is better than the 315/345 combo of PSC2 for pure grip and lap times. The only advantages of PSC2 are the longevity of the tires and ability to drive on street even in wet weather between track days.

They may not be exactly the same width, a bit wider and taller but close to the 325.

My 345 PSC2s look great after 2 days at ACS and several months of occasional street driving since that event. Also, 305 PSC2 are too narrow on ZLE 11" wheels, they look stretched.

I'll be using PSC2 for the next 2-3 events because I found a great deal on a set of barely used 305 & 315 off a GT350, so I have extra fronts--on ZL1 you need 2 front sets for every set of rears.

[TheRealJA105]

Originally Posted by ICTsccaCamaro

I've got the rear sway bar set on the soft setting and the 305/355 tire combo, but if you are stupid with the throttle mid corner the back end will step out and oversteer, this is one car that I have never had a understeer issue with.

I really need to drive a ZLE. My car is pretty equal power wise to a ZL1 and I know all to well the mid corner throttle oversteer. However i'm talking about off throttle corner entry understeer, but it sounds like a non issue for you.

[2018$S1le]

To wrap up the thread, I am installing the Kuhmo Ecsta V720 305/30-19 tires up front and as mentioned there is a bit of difference between the fronts and rears. See pics below:

[2018$S1le]

The only differences are in the traction rating and speed rating. In case you can’t see from the pics, the 355’s have a traction rating of “A” and the 305’s are rated at “AA.” Odd considering “AA” is the higher rating and that’s on the fronts. As for the speed rating, the rears (99Y) are good over 186 mph but the fronts (102W) are only good to 168 mph. The treadwear rating of 200 (which most likely varies from one manufacturer to another) suggests a 60k mile life span under normal driving conditions. Will they last that long? Not if I have anything to say about it!

[FalconerOneSeven]

Originally Posted by 2018$S1le

And here are the after:

This looks absolutely wild..
Is your 1le lowered? How much camber do you run? and how bad does it rub if rubs at all?
I picked up an Zl1 last week along some 19'' X 11'' and 19'' x 12'' OEM 1le and trying to figure out now out what tires I want to mount. Anyway many thanks for starting this very informative thread.

[2018$S1le]

Mine is not lowered and is running factory delivery spec as far as camber is concerned (so in the street setting, not track). I just got mine broke in last week so now for the real fun to begin. You do need to move the wiring harness on the driver side rear wheel well. It rubs the liner but just barely. There is a pic in this thread of where it rubs. Plenty of threads and YouTube videos covering that relocation procedure. Very simple, 30 minutes and a few zip ties will get you rerouted And in the clear. You’re welcome, glad to help my fellow Camaro gang out!

[FalconerOneSeven]

Originally Posted by 2018$S1le

Mine is not lowered and is running factory delivery spec as far as camber is concerned (so in the street setting, not track). I just got mine broke in last week so now for the real fun to begin. You do need to move the wiring harness on the driver side rear wheel well. It rubs the liner but just barely. There is a pic in this thread of where it rubs. Plenty of threads and YouTube videos covering that relocation procedure. Very simple, 30 minutes and a few zip ties will get you rerouted And in the clear. You’re welcome, glad to help my fellow Camaro gang out!

Can you run some negative camber in the back?

[2018$S1le]

Yes, see the above post by ICTsccaCamaro.

[cirpower]

If there is some rubbing at the fender under full compression with the 355 even with lots of camber, I don't think that would work for me. It seems rather dangerous and I don't want to damage the fenders and wheel liner.

I am starting to think that the kuhmo's in the front 305-30-19 and the GY 3Rs in the back 325-30-19 could be a nice and cost effective setup. But I am worried about inducing understeer.