As part of an upcoming project article, we recently installed a set of Weld Racing‘s RT-S S71 Series wheels on our Cadillac CTS-V. The CTS-V will also be receiving some new go-fast goodies from Lingenfelter Performance Enginering and a sweet-sounding exhaust from Corsa Performance.
The wheels we installed serve a number of different purposes for us. Most importantly, they are designed to be substantially lighter than the cast, heavy factory pieces, which helps to reduce rotating weight – always a good thing in a drag application for acceleration purposes. They also provide us a permanent place to mount our Mickey Thompson 295/45/17 ET Street Radial II rear tires and 26x6x18 Sportsman SR front tires so that we can perform a swap whenever it’s time to drag duty. Not to mention, they look darn good.
The RT-S series wheels (which encompass a number of different styles like the S71, the S74, and the new S75, 76, and 77 designs) are all crafted to feature minimal weight to maximize performance, and are specifically designed to fit modern muscle cars. They are designed for both street and drag applications, so you don’t have to fear leaving these on all the time – they’re engineered for that.
Each wheel center is built from hot-forged aluminum while the wheel shells are cold-forged, and a proprietary welding process is used to mate the inner and outer rim shells with the center section. Weld’s unique low, medium, and high-pad options are available on all RT-S wheels for the wheel center sections, and they are able to provide a number of fitments of the same design to fit different types of OE and aftermarket braking systems.
Our application required the high pad design to clear the Brembo brakes on the CTS-V. The low-pad option has a wheel face that’s nearly flat to go with a shallow mounting surface, while the high pad option centers have much more curvature to the wheel spoke to go along with a thicker mounting surface in the center of the wheel.
As you might expect, the mid-pad design occupies the middle ground between the other two. By constructing the wheel centers in this fashion, Weld can come up with a wheel to fit just about any type of braking system on the market today.
According to Weld’s Chris Bovis, “We’ve worked very hard with Ben at Weapon X Motorsports on the wheel fitment for the CTS-V. Ben put a lot of time and effort into making sure this fitment was correct and produces the results that CTS-V owners are looking for. Using the different pad designs allows us to have more flexibility to curve the spokes of the wheel to get the wheel/tire/fender clearance that people are looking for. We actually have three separate forgings for the S71 design.”
The CTS-V wears 17×10-inch rear wheels with a 7.2-inch backspace [PN 71HP7100N72A, MSRP $471.54 each] and 18×5-inch front wheels that have a 2.1 inch backspace [PN 71HP8050N21A, MSRP $556.80 each]. These wheels offer the option of a polished or black-anodized wheel center to go with the polished rim shells, which allows you to pick the wheel that will look best with your paint scheme. They are built in the USA, right in Kansas City, Missouri, using premium materials and the latest in computer-aided design techniques. Weld’s winning tradition in motorsports extends into every single wheel they make; whether it’s for a street car like ours or a Top Fueler, they bake in the same quality and long-lasting performance.