Make Your K5 Chevy Blazer Perform With A TCI Chassis

The popularity of GM’s 1967-1972 truck line has flowed over into Chevrolet’s K5 Chevy Blazer offerings as well. Introduced in 1969, the K5 Blazer was a strong competitor in the early SUV market and sales swiftly outpaced other manufacturer’s offerings. Thanks to a resurgence in the popularity of GM’s fourth generation of heavy haulers, the short-wheelbase K5 Blazer and Jimmy variants have also enjoyed a new-found loyalty from both enthusiasts and the aftermarket. The latest product to hit the K5 Chevy Blazer scene is three new chassis designs now offered by Total Cost Involved (TCI) Engineering.

The K5 Blazer chassis was just a natural progression in our evolution of creating components that enthusiasts want. There is such a broad spectrum of customers, including off-road, hot-rodders, slammed, and pro-touring! – Jason Wilcox, TCI Engineering

The folks at TCI Engineering have been providing American-made suspension parts for street rodders, hot rodders, and muscle car enthusiasts since 1974. The company continues to innovate and offer a variety of suspension components to update and tailor a vehicle’s performance. This latest offering comes in the form of a complete K5 Chevy Blazer chassis, engineered as one of three different options to suit the vehicle’s intended purpose. Enthusiasts can choose between TCI Engineering’s Classic, Pro-Touring, or the oh-so-low Grounded chassis for their Chevy.

K5 Chevy Blazer frame

The Classic K5 Chevy Blazer Chassis

TCI Engineering’s Classic chassis features modern technology such as rack-and-pinion steering and coilover suspension, but there is much more than just bolting on some popular products. These complete chassis remove the ancient technology these vehicles left the factory with and replace it with modern-era designs and engineering so that it handles like a modern muscle car.

The geometry built into the TCI Engineering chassis was grafted-in from years of research and development in racing and will allow your K5 Blazer to do everything better. TCI Engineering’s Jason Wilcox puts it this way, “The chassis will be very compliant, very comfortable. It will do everything a modern car will do and the best part, it is going to turn when you want it to!”

When you compare TCI Engineering’s frame with the original, you’ll note how the company’s engineers have widened the rails ahead of the cab and narrowed them behind the cab. This modification allows more room for headers and steering components at the front and moves the shocks outside of the frame rails to better maximize roll stiffness.

Frame rails are cut out of plate steel and seam welded in a fixture to ensure consistent thickness throughout. All weld edges are carefully ground and smoothed. Any deviations in weld height found during this process require the frame rail to go back to the welding station.

Each frame rail begins with eight laser-cut pieces of steel that are then fixture-welded. The rails are then placed in a jig while adding the center section and various crossmembers to ensure each chassis is sturdy and square. The center section of each frame is comprised of 12 pieces of steel and allows for a three-inch round tube exhaust with ease.

Every chassis is welded in a sophisticated, vehicle-specific fixture where the frame rails are fully captured from front to back. TCI Engineering has built its frame fixture as a three-piece modular unit which allows them to adapt it for 12 different versions of a chassis. TCI Engineering’s tight tolerances ensure the cab, core support, and bed will bolt on without drama.

The 1969-1972 Classic K5 Blazer chassis uses TCI Engineering’s Pro-Touring IFS at the front. The front crossmember is moved forward to center the front wheel in the wheel openings and is raised to provide for more ground clearance at ride height.

The TCI Engineering IFS serves as the base for each of the three chassis. Both the Classic and Grounded chassis use a four-bar configuration for the rear suspension.

The Classic chassis’ rear suspension consists of TCI Engineering’s proven four-link which holds a complete Currie Enterprises 9-Plus 9-inch-style rear housing. A brand-new Currie 9-Plus nodular third-member is included with each complete chassis from TCI Engineering. As with the front suspension, the rear of the chassis features adjustable coilovers which allow for fine-tuning of the vehicle’s ride height and handling characteristics.

Pro-Touring Blazer Chassis

As you can imagine, TCI Engineering’s Pro-Touring chassis for the 1969-1972 K5 Chevy Blazer includes the company’s tried and true Pro-Touring IFS suspension at the front of the frame rails. Where the corner-carving magic really starts to happen is with the inclusion of TCI Engineering’s torque arm rear suspension. The torque arm is designed to provide unmatched stability while eliminating suspension bind when cornering. There is a telescoping slider on the torque arm that allows the suspension to move freely throughout its full range of motion.

The telescoping slider at the leading edge of the torque arm allows bind-free articulation and plunge during travel. The left-hand and right-hand pinion bars make adjustments to the pinion angle a breeze.

The entire Pro-Touring chassis is designed for its intended purpose and each of the frame rails has been raised 8 inches in the rear to allow for an extremely aggressive ride height and low center of gravity. The narrowed frame also allows for massive 335/30/R18 tires at each corner, which will typically put the frame rails 4 to 4 1/2 inches off of the ground. The Pro-Touring chassis allows for a lowered stance, greater rear axle control, and dramatically improved handling.

TCI Engineering’s Grounded Chassis

TCI Engineering’s K5 Blazer grounded chassis is also a highly-engineered suspension and is designed to be the best for its intended purpose. Based on the increasingly popular airbag suspension, the engineers at TCI Engineering spent countless hours making sure the chassis performed as needed while meeting performance expectations. When fully aired out, the suspension allows for that “in the weeds” look. Fully aired, the suspension allows for a maximum ground clearance of 8 inches with minimal camber change.

When designing the grounded chassis, the goal was to be able to run the least amount of pressure in the bags to keep the vehicle at ride height. Up front, the Pro-Touring IFS is converted to use airbag mounts with Ridetech single-adjustable shocks mounted outboard of the frame rails. Out back, the frame rails are raised eight inches and also C-notched to provide clearance for that slammed look.

TCI K5 Chevy Blazer frame

Each of the Blazer chassis features a 12-piece center section that provides strength and rigidity. A built-in driveshaft loop adds another level of safety to the design. All TCI Engineering frames feature the necessary cab, bed, bumper, and core support mounts for each application.

The grounded chassis uses TCI Engineering’s four-link suspension featuring Currie Enterprises “Johnny Joints” for complete articulation throughout the suspension’s broad range of travel. The rear suspension is engineered to limit pinion angle during suspension cycling and minimize forward movement of the axle’s centerline at full compression. As an added value, all TCI Engineering K5 Blazer grounded chassis come fully plumbed with 1/4-inch stainless air lines and 3/16-inch brake lines and hoses. You just need to add your own air management system to complete the installation.

Upgrade To A Perfect K5 Blazer Chassis

Thanks to the scope of each of TCI Engineering’s K5 Blazer chassis, you can order a suspension suited specifically to your application. What’s more, TCI Engineering also offers several upgrades to any of their chassis to improve the already impressive performance.

There are several options when ordering a TCI Engineering suspension, such as larger Wilwood brakes, rear sway bars, or a positraction rear differential.

While TCI Engineering’s custom spindles are supplied with 12-inch rotors and calipers standard, they can be upgraded to 13- or 14-inch Wilwood brakes with six-piston calipers in front and a four-piston setup in the rear. A Currie F9 sheetmetal rear axle housing is available in your choice of gearsets ranging from 3.00 to 4.56:1 and a TwinTrac Posi unit is also available as an upgrade. We recommend contacting one of TCI Engineering’s sales staff to ensure that your chassis is built exactly to your specifications.

All TCI Engineering products are covered by TCI Engineering’s Dual Warranty. The Dual Warranty means there is a six-year, 60,000-mile warranty on wear and tear items such as bushings, tie rods, and ball joints. Any items built in-house by TCI Engineering such as link bars, control arms, spindles, crossmembers, etc come with a lifetime warranty. You can be sure that those parts will not only give you great performance but will continue to do so for a long time.

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About the author

Andy Bolig

Andy has been intrigued by mechanical things all of his life and enjoys tinkering with cars of all makes and ages. Finding value in style points, he can appreciate cars of all power and performance levels. Andy is an avid railfan and gets his “high” by flying radio-controlled model airplanes when time permits. He keeps his feet firmly grounded by working on his two street rods and his supercharged C4 Corvette. Whether planes, trains, motorcycles, or automobiles, Andy has immersed himself in a world driven by internal combustion.
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