[Fuzzman66]

I have a 2017 SS Fifty Edition. I just installed a new set of wheels and tires on the car. The new front wheels are 10.5 x 20 (26mm offset) with 285/30/20 tires and rears are 11 x 20 (40mm offset) with 305/30/20 tires. I believe this is a very similar wheel and tire set up to an OEM SS with the 1LE package although my front wheels are .5" wider.

When I put them on the car the fitment seems to be correct...brake and fender clearance is good. However, for some reason the front ride height now appears to be too high. I took a quick measurement and the gap between the front fender and tire is 1" larger than the gap between the rear quarter panel and rear tire.

Is this a common issue that you all have seen with Camaro SS owners going from an OEM wheel and tire set up to the 10" or 10.5" front wheels with the 285 width tires? If so perhaps there is a quick fix to get the front end to sit down with the proper gap? I'm assuming it should be the same as the rear which it seemed to be with the OEM wheels and tires.

Thanks.

Matt

[Nothing like an SS]

1LE rears are taller than the fronts, sounds about right.

30% of 285 vs 30% of 305 for sidewall height

[Fuzzman66]

Makes sense to me but shouldn't the gap between the top of the tire and the corresponding body panel be consistent front to back? It certainly was when I had the OEM wheels on the car.

[clyde]

You drove/moved the car after putting on the new tires so the suspension could settle, right?

[arpad_m]

Originally Posted by Fuzzman66

Makes sense to me but shouldn't the gap between the top of the tire and the corresponding body panel be consistent front to back? It certainly was when I had the OEM wheels on the car.

Not really, you reduced the overall tire height in the front much more than in the rear, both compared to stock. Those magnetic 1LE shocks and the springs must have been chosen and tuned to account for the difference on the 1LE with the same tire specs.

What you can do if you are very disappointed with the gap is lowering springs in the front, or you can just live with it (and maybe buy 275/35/20 tires next time).

[Nothing like an SS]

Originally Posted by arpad_m

Not really, you reduced the overall tire height in the front much more than in the rear, both compared to stock. Those magnetic 1LE shocks and the springs must have been chosen and tuned to account for the difference on the 1LE with the same tire specs.

What you can do if you are very disappointed with the gap is lowering springs in the front, or you can just live with it (and maybe buy 275/35/20 tires next time).

Yes, the 1LE has a lowered suspension, plus the magna ride, which does have different geometry. That could indeed cause the difference in the height on a non-1LE.

GM has the full lowering kit for the car as well, few threads around here on that.

[Fuzzman66]

I think you guys are correct that the size of the front tires are off. The OEM front tires are 245/40/20 with a diameter of 27.7 inches. The 285/30/20 tires have a diameter of 26.7....an inch smaller. That has to be the issue, and it's going to be a problem as I'm sure it will throw off the speedo, odometer, etc. I think I can fit a 275/35/20 tire on the 20 x 10.5 wheels and the diameter of the tires are 27.6...really close to OEM spec.

[arpad_m]

Originally Posted by Fuzzman66

I think you guys are correct that the size of the front tires are off. The OEM front tires are 245/40/20 with a diameter of 27.7 inches. The 285/30/20 tires have a diameter of 26.7....an inch smaller. That has to be the issue, and it's going to be a problem as I'm sure it will throw off the speedo, odometer, etc. I think I can fit a 275/35/20 tire on the 20 x 10.5 wheels and the diameter of the tires are 27.6...really close to OEM spec.

The speedo is based on driven wheels, and you're still within ABS and stabilitrak tolerance with your current setup (otherwise you'd be seeing ABS and traction control lights in the dash and drivability would be compromised), so IMO there is no urgent need to fix anything. You must have spent a lot on the wheels+tires already, just change up the front tires next time you need a set.

[wnta1ss]

Originally Posted by Fuzzman66

I think you guys are correct that the size of the front tires are off. The OEM front tires are 245/40/20 with a diameter of 27.7 inches. The 285/30/20 tires have a diameter of 26.7....an inch smaller. That has to be the issue, and it's going to be a problem as I'm sure it will throw off the speedo, odometer, etc. I think I can fit a 275/35/20 tire on the 20 x 10.5 wheels and the diameter of the tires are 27.6...really close to OEM spec.

Speedo comes from the trans (therefore rear tires), not the front tires, so don't worry about the 285/30-20 affecting that. The 305/30-20 tires on the back will just slightly raise the speedometer readings, because they are a little shorter than the 275/35-20s that you removed.

[Nothing like an SS]

Originally Posted by wnta1ss

Speedo comes from the trans (therefore rear tires), not the front tires, so don't worry about the 285/30-20 affecting that. The 305/30-20 tires on the back will just slightly raise the speedometer readings, because they are a little shorter than the 275/35-20s that you removed.

And all is the same as a stock 1LE, so all good, well within the tolerance and will not cause any issues.

[Fuzzman66]

Appreciate all of the insights guys. Thank you.