Forgeline SO3S VS SO3P

[bob waters]

I have been searching through the old posts/threads and found the wheel I really like. The Forgeline premier SO3S. There are lots of pics of this wheel years back on this site and other sites in 18". I really like the step lip. The ones I saw were 18" and now I only see 19" in the step lip. Am I correct to think the step lip will give more rigidity to the wheel rim? The SO3P is nice but at the price I am looking for exactly what I want and that is an 18". The wheels will be going on a 1970 Camaro. 18x10 front and 18x12 rear.

[Forgeline Wheels]

I have been searching through the old posts/threads and found the wheel I really like. The Forgeline premier SO3S. There are lots of pics of this wheel years back on this site and other sites in 18". I really like the step lip. The ones I saw were 18" and now I only see 19" in the step lip. Am I correct to think the step lip will give more rigidity to the wheel rim? The SO3P is nice but at the price I am looking for exactly what I want and that is an 18". The wheels will be going on a 1970 Camaro. 18x10 front and 18x12 rear.

Hi Bob,

The SO3S is the exact same center as the SO3P. But on the SO3S, that center is bolted into a set of standard stepped lip rim halves, whereas the SO3P is bolted into a set of reverse flat lip rim halves.

But it is important to remember that a standard stepped lip rim adds one inch to the total outside diameter (because that step is a half inch taller all the way around). And the smallest diameter that we make the SO3S/SO3P center is 18 inches. So if we bolt that 18 inch center into a flat lip reverse rim, it ends up being an 18 inch wheel, and we call it the SO3P. But if we bolt that same 18 inch center into a stepped lip standard rim, then it ends up being a 19 inch wheel, and we call it the SO3S.

In order to offer the SO3S in an 18, we'd have to make a 17 inch center. And we probably won't do that, because the investment in new forgings and engineering time just wouldn't be worth it. So the stepped lip SO3S is only available in 19, 20, and 21 inch diameters.

HOWEVER, I have three other suggestions for you for 18 inch 5-spoke wheels that are very similar to the SO3S:

1. The SO3. This wheel is VERY similar to the SO3S (hence the names), but has a slightly different angle where the spokes connect with the rim register. See: http://www.forgeline.com/products/so3-17-18.html

https://static1.pt-content.com/images/pt/2017/11/0Ft1dZh-1.jpg

2. The GF3. The GF3 is our newest 5-spoke design. This wheel is actually load rated at 2100 lbs each using the SAE's standard friction coefficient for "street" tires, so it is better suited than the SO3 or SO3S for serious track duty. See: http://www.forgeline.com/products/gf3-18-19-20.html

https://static1.pt-content.com/images/pt/2017/11/dCifVev-1.jpg

3. The GF3 Open Lug. This is the same as the GF3 (above), except the center lug area has been machined out to reduce weight and provide better access to the lug nuts for faster/easier wheel changes and brake service. See: http://www.forgeline.com/products/gf3-open-lug.html

https://static1.pt-content.com/images/pt/2017/11/RS0Xg3y-1.jpg

[Bigoil]

What face finishing is that last wheel ? ☝��

[Forgeline Wheels]

What face finishing is that last wheel ? ☝��

This GF3 Open Lug is Gunmetal.

https://static1.pt-content.com/images/pt/2017/11/RS0Xg3y-1.jpg

[bob waters]

Thanks Mark great info.