[TrackClub]

Great info and pix, so thanks for the posts!
Goodyear tread ratings aside, just looking at the G3R rubber it looks like a friggin slick
Another member has had good longevity from R7s - 6 days I think? Ref Official Video thread for details. He did 2:08.x at the Glen on them, so he also surely knows how to drive.

One question, as it seems that GM updated some bits in the HP Supplement for 2018 and I can't get an online cc of it from MyGM:
Are recommended cold pressures for G3 26psi?
I believe my 2017 HP Supplement recommended 28 (can't double check as I am tons of miles away from my 1LE for the winter). Thank you!

[seanblurr]

Sorry if I missed this, but was the RF delaminating and showing cords after only 1 day?

Disregard, looks like you got 14 heat cycles spread across 3 events. That's not terrible for an R comp on a 3800lbs car... The delamination is a concern though, as I've seen others mention this after 1-3 events as well.

[Chris V]

Originally Posted by RUQWIKR

No spacers, just profile ground where the rim would contact the laminated steel area. No pics, but, red circled area is where you need to grind.

Thanks!

[JRL1LE]

Thanks, RUQWIKR, great data!

[RUQWIKR]

I also wanted to add that we got a Green flag at about a half out-lap, but, it took about 2 laps to feel up to temp. Neither seemed to fall off much, if at all, at the end of the sessions. I have heard that max temp is around 220F for tread. I am going to buy a touch / needle pyrometer as I have been told to use one of those instead of my laser version.

Originally Posted by TrackClub

Great info and pix, so thanks for the posts!
Goodyear tread ratings aside, just looking at the G3R rubber it looks like a friggin slick
Another member has had good longevity from R7s - 6 days I think? Ref Official Video thread for details. He did 2:08.x at the Glen on them, so he also surely knows how to drive.

One question, as it seems that GM updated some bits in the HP Supplement for 2018 and I can't get an online cc of it from MyGM:
Are recommended cold pressures for G3 26psi?
I believe my 2017 HP Supplement recommended 28 (can't double check as I am tons of miles away from my 1LE for the winter). Thank you!

As per earlier:

Starting and hot pressures for both tire types:
G3: 26psi starting and 32 - 35 hot for both front and rear
G3R: 28psi starting for both front and rear but hot pressures 35 – 37 front and 37 – 39 rear

Originally Posted by Ryephile

10-4, thanks. Even if the tire's gave only half that time, it's still a big improvement.

It seems our 1LE's would greatly benefit from stiffer anti-roll bars to keep the dynamic camber in check. That would definitely improve the tire wear (and grip from using the whole tire instead of being on the shoulder so prominently).

Anyone try any yet, and if so, what combo? As I replied to you in another post with specs, the ZL1 1LE bars are much lower stiffness rate than our bars.

Originally Posted by seanblurr

Sorry if I missed this, but was the RF delaminating and showing cords after only 1 day?

Disregard, looks like you got 14 heat cycles spread across 3 events. That's not terrible for an R comp on a 3800lbs car... The delamination is a concern though, as I've seen others mention this after 1-3 events as well.

Someone posted pics of the G3R with outside delam but I did not search too hard for that thread. Forgot to take a pic before I tossed it in the dumpster, but, it looked like that guy's front tire(s).

I can see why folks love R-compound and race slicks, but, it's still eye opening on how easily it is to spend big bucks on tires alone with a fast heavy car.

[seanblurr]

I think what trackclub is getting at is the apparent change in pressures for the regular G3's. The 17's supplement lists 28psi cold with a target hot pressure of 35-37psi. It's odd that GM would update the manual less than a year later for the same tire by a whopping 2 psi.

[RUQWIKR]

Originally Posted by seanblurr

I think what trackclub is getting at is the apparent change in pressures for the regular G3's. The 17's supplement lists 28psi cold with a target hot pressure of 35-37psi. It's odd that GM would update the manual less than a year later for the same tire by a whopping 2 psi.

In the electronic Service Manual: 2017 & 2018 SS 1LE and ZL1 (non-1LE) shows 28psi cold starting for both front & rear. The printed manual that GearheadSS posted last November shows 28 as well on page 16.

https://drive.google.com/drive/folde...C1RT0cwVS1xakk

[TrackClub]

Originally Posted by seanblurr

I think what trackclub is getting at is the apparent change in pressures for the regular G3's. The 17's supplement lists 28psi cold with a target hot pressure of 35-37psi. It's odd that GM would update the manual less than a year later for the same tire by a whopping 2 psi.

Thank you Sean that's exactly my point.
I am also surprised the Rs would be recommended to run higher pressures as usually Street Rcomp vs Slick would be a reverse of that. I wonder if some manual editor maybe got it in reverse???
As to the delamination issue, they did say they were *CUP* tires, eh? LOL

OP: thanks for re-confirming. May I ask if both were listed in the same HP Supplement, or two different ones? Thanks again!

[TrackClub]

Originally Posted by RUQWIKR

In the electronic Service Manual: 2017 & 2018 SS 1LE and ZL1 (non-1LE) shows 28psi cold starting for both front & rear. The printed manual that GearheadSS posted last November shows 28 as well on page 16.

https://drive.google.com/drive/folde...C1RT0cwVS1xakk

OK so I am completely confused now.
Given the above still recommends 28 for G3 then WHICH source recommends 26?
Thanks!

[RUQWIKR]

Originally Posted by TrackClub

Thank you Sean that's exactly my point.
I am also surprised the Rs would be recommended to run higher pressures as usually Street Rcomp vs Slick would be a reverse of that. I wonder if some manual editor maybe got it in reverse???
As to the delamination issue, they did say they were *CUP* tires, eh? LOL

OP: thanks for re-confirming. May I ask if both were listed in the same HP Supplement, or two different ones? Thanks again!

Originally Posted by TrackClub

OK so I am completely confused now.
Given the above still recommends 28 for G3 then WHICH source recommends 26?
Thanks!

I confused myself and corrected my original info. I just read / typed wrong - below should be correct: - sorry. That was a lot to type this morning. Hopefully, all is well with you seasoned guys now on this!

Per HP Supplements, starting and hot pressures for both tire types:
G3: 28psi starting for both front and rear cold with and 35 - 37 hot front and 37 - 39 hot rear
G3R: 26psi starting for both front and rear cold with 32 – 35 hot front and rear

[seanblurr]

Ok, that's what I was thinking you meant to say. Thanks for the fix.

[Ryephile]

Originally Posted by RUQWIKR

...Anyone try any yet, and if so, what combo? As I replied to you in another post with specs, the ZL1 1LE bars are much lower stiffness rate than our bars.....

Not that I've seen, but I'd surely like to. I know you mentioned the ZL1 1LE bars elsewhere, but I didn't see any sourcing to back it up. Also, I PM'd BMR for some data and they replied saying they're working on getting us the numbers between FE4 bars and their offerings.

The important part is getting the dynamic wheel rate higher to get the car flatter in corners to improve tire wear.

[RXtacy]

According to TEX1LE here are the rates. Maybe he'll chime in where he got them.

Originally Posted by TEX1LE

yeah the rates are a lot higher if you get the adjustable. The rates aren't listed but if you watch the video the guy gives the different rates.

Stock rates (1LE): Front 397lbs / Rear 169 lbs

BMR: Front 596/702/840 lbs
Rear 300/342/395 lbs

[Ryephile]

Huh, I have it saved in a text doc that BMR quoted the 397 lb/in front and 169 lb/in rear rates are FE3 anti-roll bars, but I forgot to put a link to source it.


There's this post where they explicitly state they haven't gone through the FE4 rates yet.