Innovation is a constant progression, not a destination. That is why Speedtech Performance went a step further and made its ExtReme series subframe for Gen I and Gen II F-bodies and C2 Corvettes just a little bit more – extreme. Starting with a design that has been hugely popular with the pro-touring crowd, Speedtech added even more benefits to its ExtReme suspension kit by taking something away — weight. Other benefits include improved cooling and steering geometry.
Speedtech has re-designed its ExtReme-XS suspension to utilize integral ductwork to direct airflow onto the brakes without taking away any room for meaty tires up front.
Starting with a proven design in the ExtReme series, the engineers at Speedtech Performance began upgrading the suspension and named it the ExtReme-XS series. Both ExtReme suspensions deliver the ultimate in performance and control, but Speedtech has designed the “XS-Series” suspension to be just as rigid, and much lighter. The ExtReme-XS front subframe for Gen-I and Gen-II F-bodies is 20% lighter than the previous ExtReme series.

The ExtReme-XS subframe is engineered for reduced weight while keeping the rigidity necessary for ultimate performance.
Additional Benefits Of Extreme-XS
We all know how beneficial weight savings can be when hundredths of a second are on the line during competition, but the folks at Speedtech didn’t stop there. The ExtReme-XS chassis is packed with additional benefits such as an integrated path of airflow to brake cooling ductwork. This new design gives your hard-working brakes that breath of fresh air they need during the heat of competition. Airflow is directed within the cavity of the frame rail and exits with a straight path via flexible ductwork to the brake rotors. Amazingly, the addition of this cooling pathway does not restrict the available space for asphalt-grabbing tire sizes. No body modifications are necessary to fit a 315/30/18 tire up front while still retaining a 30-degree steering angle.
Beyond the benefits of the ExtReme-XS design, customers will also receive all the performance-enhancing upgrades designed into the ExtReme chassis. The suspension’s alignment settings are still fully adjustable and there is nearly zero bumpsteer so what you set is what you get throughout the entire suspension’s travel. There is also a maintenance-free wheel bearing bolted to each forged, 7075 aluminum spindle and the power rack-and-pinion steering is a vast upgrade over the OEM steering box.
Just like the ExtReme series, the ExtReme-XS suspension is a bolt-in component of the unibody for F-body vehicles and an integral component of the frame on C2 Corvettes. With the ExtReme-XS series, 1967-1981 F-bodies and C2 Corvettes will get all the performance customers have come to expect from Speedtech Performance. They also get the added benefit of a 20-percent reduction in sprung weight. Speedtech Performance’s ExtReme-XS is a perfect example of how taking something away can actually increase the value for the end user.