DETAILS:
At first, offsets can be very tricky to understand. We promise you, they are not. Usually referred to as “ET” by manufacturers in the industry, in simple terms offset is the distance between the centerline of the wheel and the mounting surface. The lower the offset, the more the wheel will stick out. The reverse is also true, the higher the offset, the more the wheel will tuck in. The whole point of an offset is for the enthusiast to know how much in inches or in the case of millimeter offset, how many mm the wheel will stick out or suck in from the mounting surface.
Typically, factory wheels will run a high positive offset, usually in the +30mm to +40mm range. This allows the wheel to squeeze into the wheel wells more, keeping your center of gravity under the cockpit and reduces the overall width of your car. The problem with a +30mm and higher offset is that the hub is so close to the front of the wheel, there’s little to no room for creative wheel design. The deep dishes and aggressive spokes can’t happen with only 2 inches of room. Reverse the offset (-45mm) and now you have some space to get creative with the wheel design.
Here at Need 4 Speed Motorsports , we’ve developed this incredible offset calculator tool that allows you to take your current wheel specs, your new wheel specs, and see how they compare in real-time. The best part? It’s very easy to use. All you need are your current wheel widths and offsets and your new wheel widths and offsets. And you can do front and rear setups at the same time! Here’s an example:
In the example above, we see here that the current front wheel set up is a wheel that’s 9″ wide with a +45 offset. The new wheel will be 10″ wide with a +35 offset. The results are 3mm less of inner clearance and it will extend 23mm outward. So, to break that down even further, the new wheel will move into this particular car’s wheel well an additional 3mm inward toward the suspension parts while coming outward toward the fender 23mm. For the rear, it’s a little bit different. The old wheel was 9.5″ wide with a 52.5mm offset, and the new wheel is going to be 11″ wide with a 50mm offset. This results in 17mm less of inner clearance, and 22mm more of an outward extension.
This does not answer whether or not a specific wheel will fit on your car, but it will give you the data you need to be able to measure your own car and see if you do have an extra 3mm of space inward, or if 23mm outward will poke past your fender etc.
A video on this will be coming out soon but until then, please feel free to reach out to us regarding any wheel, tire, and fitment questions you might have.
Follow us on Instagram and Facebook.
Send us an email for fitment and pricing info info@n4sm.com
Call our store 1-888-714-7467
