View Single Post
Old 01-25-2019, 12:48 PM   #17
Shawnqa800720
 
Shawnqa800720's Avatar
 
Drives: 2018 1SS
Join Date: Dec 2018
Location: MA
Posts: 300
Quote:
Originally Posted by vtirocz View Post
I'd still like to hear the Camaro team's input on this one.

I did get some additional info straight from GM on this topic that I wanted to share (around tuning for different tire sizes). I reached out to Jordan Garwood (Product and Marketing Manager: Performance Parts – All Vehicles
Performance Vehicles, Accessories, & Motorsports) on what it would take to put SS 1LE wheels/tires on my SS and calibrate for the different diameters:

"Unfortunately we (GM) don’t have a way for a dealer to do this [calibrate tire size or rev/mile] so it would require an aftermarket handheld tuner. Vehicle calibrations are specific to VINs and a dealer cannot put the cal from 1 VIN (1LE) into another VIN (SS). I can’t really say since these aren’t “manufacturer approved” vehicle calibration updates. I bounced the cal question to another Engineer I know, who was a Camaro test driver previously, and his reply is below:

Confirmed that we do have two different cals (SS & 1LE) for the speedo. We will have different cals for the ABS/TC/ESC for the different vehicles as well due to the tire and suspension differences. The lowering kit for the SS is meant to work with the SS tires. Should a customer choose to put the 1LE tires on the vehicle, the vehicle will have speed and odometer errors along with less optimized Chassis Control Cals. They may even risk voiding the vehicle warranty with this change.”

Of course the Performance Suspension Kit is designed to integrate perfectly with your stock SS vehicle and cals, but it sounds like the 1LE wheel and tire change is more challenging than even I would have anticipated since there is no “factory” calibration solution available and you would therefore need to find a tuner for more than one of your vehicle calibrations.

I agree the wheels would look great but it sounds difficult to get the exact calibrations needed to realize the desired performance benefits you are seeking.

So, even though this may not be the answer you wanted, hopefully it points you in the right direction should you decide to pursue.

Thanks again for your passion for your Camaro and all your interest in the Performance Suspension kit.

Hope this helps!"


I'd still really like to hear from the Camaro team what tire size differences (or front to rear ratio differences) start to matter from a ABS/TC/Stability control standpoint.

NICE job doing your homework Vtirocz! One thing to ask if you get time with your sources again is the fact that the Camaro team did pair the 1LE wheels in the testing that Team Camaro performed in answer to your Ask Al question. I would assume they had the same information about tire size against control systems programming, and went forward with it anyway. Now the question is, did they reprogram for the 1LE wheels, or did they deem the change not impactful enough to bother with it??

I was honestly afraid of that answer though. With all the control systems these vehicles have and how well thought out they are, I'd have been pretty surprised if they didn't account for wheel size. With that said, it is obvious lots of folks have made these changes, and relatively little ill effect, but I'd assume in the hands of very experienced drivers, they may catch the issues.

What I am really curious about now is whether it is diameter ratio or absolute diameter that will impact the control systems. I don't really care if the speedo is off a bit. I do care if the control systems are off. My logic is telling me that keeping the ratio is the more important piece of the puzzle, but even there, if the algorithms are taking speed of the car into account against tire rotation speed / revs/mile, that could impact the correction measures the nannies would try to make. What a PITA! I guess I'm back to my exercise of finding the right tire/wheel alternate combo to keep closer to the absolute diameter and diameter ratio

I have until March-ish to get this answered as that is when the weather will start to break here, and I'll be looking to get the new tires on. Who can we pester to get this out to Team Camaro - I would assume wheel changes are one of the most common modifications, and if there is a potential negative effect, this should be broadcast
__________________
2018 Red Hot 1SS, GM lowering kit & 1LE Sway bar kit, ZL1 1LE solid rear cradle bushings, BMR sway bar end links, GM CAI w/tune, Pray ported IM, Mamo ported TB, VS Forged VS07 rims 20x11 & 20x10 w/ Michelin PS4S
Shawnqa800720 is offline   Reply With Quote