949Racing is a small race equipment shop in Lake Forest, CA. No bling, just speed
The story of the 6UL
This project started a few years ago when I realized there was no reasonably priced 15x8" pcd 4x100 +40 wheel that fit my import. So with the help of some experienced wheel engineers, I designed my own and started 949Racing to offer them to you. Every detail was sweated to create the best possible strength to weight ratio with the 6UL. We now have several new sizes and more on the way.
While the 6UL looks similar to some other wheels but not exactly like anything, it's because it is different. The design is an evolution of a 15x8 centerlock race wheel developed for the Radical SR8. Unlike so many other import wheels, the 6UL is not a copy of anything.
Hub rings and bore center
You may notice there are no hub centering rings offered and there is a reason for that. Most aftermarket wheels use a generic 67 or 73 mm bore. The reason for that is to save money on tooling and machining setup time. Bigger 5 lug wheels use the big 67/73 bore so the smaller 4x100 pattern wheels get it whether it's optimum or not. The 6UL is only 59.1 which makes it a stronger and lighter wheel. Our experience is that centering rings are not needed to properly locate the wheel concentrically.
This is a biggie. The 6UL is designed expressly for the 4x100 pattern. You'll notice the center hub area is not large enough diameter to add the larger 114.3mm pattern. This is because no compromise in the 4x100 optimization was made to accommodate the larger pattern. A 4x114.3 also has a minimum allowable load capacity about 20% higher than a 4x100. This means the 6UL would have needed to be 15.36 lbs with the same relative strength. No way. A 5x114.3 about 30% more. You get the idea. If anything, the 6UL is overbuilt for a 4x100, that's because it's a race wheel which will be pounded on a lot harder than any street wheel.
You may also notice the lip is not a wide as some other import wheels, again for a reason. The best possible wheel structure has the spokes running straight from the mounting pad to the bell (outer rim). By bending the spokes back to create an artificially wide lip you add more material than is needed and weaken the basic structure. Straight spokes, smaller lip = strong and light.
The wheel was designed to have radial clearance for 11.5" rotors (outer rim). Axial clearance (spokes) depends on brake caliper offset. Notice how the distance between the spoke where they meet the rim is even where many similar design have the spoke in close pairs with uneven gaps between them. By making these gaps between the spokes symmetrical the rim between them was better supported. Thus we were able to reduce the drop center making the outer rim thinner. This not only looks nice but serves the purpose of increasing room for oversize rotors.
This makes it possible to perform a complete nitrogen purge. You may notice many high end tires stores now offer nitrogen. Nitrogen doesn't fluctuate pressure as much as your tires get hot and they hold air much longer. With a single valve, you still have some atmosphere in there when inflating with nitrogen. Two valves= 100% nitrogen.
We know that a lot of drivers want a wheel that allows the tire to be flush with the fender. The problem with that is that it allows the fender to shred your expensive tires if you lower the car and drive it hard enough to compress the suspension. Lower offset wheels usually require smaller tires to clear the bodywork resulting in less rubber on the road. Any racer will tell you more rubber means more grip, simple and irrefutable. So the 6UL's are higher offset than usual, to allow the fattest tires to squeeze under the fender at the lowest ride height on most imports. Some cars have enough room with the 15x9 6UL for a monstrous 275/35/15!
Everthing about the 15" 6UL is different, for a reason.
- 67.1 hub center (Mazda 54.1, Honda/Toyota 56.1, E30/Mini 57.1, Nissan 59.1)
- 60* conical seat lug hole (accepts stock lugs)
- Double valve design (purge valve for nitrogen)
- Low Pressure cast, monoblock
- 450kg max load
- A356.0 alloy
- T6 Heat treated
- Spectrometer analysis of raw material to insure purity
- Each batch is X rayed for material conformity
- ISO/TS 16949:2002
- JWL certified