Project Payback GTO Levels Up with a S&W Roll Bar and C&R Radiator

Welcome back to the latest chapter of Street Muscle’s build, “Project Payback,” a 1968 GTO we sent off to Pro Touring charm school. It is undergoing a transformation from an awkward junkyard dog to a poised, state-of-the-art track terror and street cruiser. In our last episode, we suited up the old GTO with beefy wheels and tires and now we’re tackling a roll bar installation to truss up this old Tin Indian and keep her cool under the collar with a new heavy-duty radiator.

This Poncho won’t be a garage queen. The idea is to build a reliable, classic GM A-body that will look and sit right, with some serious go-fast hardware that the owner and his entire family can enjoy.

We trailered the GTO to Funkhouser Race Cars in Ramona, California with a list of mods which included an S&W four-point roll bar, a custom intake tube, and a radiator install with fabricated mounting hardware. Funkhouser Race Cars is well known in the performance car scene as one of the premier fabrication shops in SoCal. They combine Solidworks 3-D design know-how, onsite CNC milling machines, and years of old-fashioned metal bending skills to outfit any performance machine with the custom-built speed and safety components you’re looking for.

Funkhouser Race Cars marries old-school skills with modern methods. What do you need?

With the formalities and introductions out of the way, let’s dive into the roll bar installation. Project Payback is running a very stout Schwartz Performance chassis as its foundation, but we wanted a roll bar to stiffen up the ancient body structure, and add anchoring points for a racing harness. We know the dual A-arm front and four-link rear suspension with Ridetech coilovers will perform best with a happy marriage of a rigid body and frame combination.

We went with S&W’s 4-Point Street bar which includes the main hoop, harness bar, rear runners, and four (4) floor plates. The S&W roll bar is a beautifully made setup with 1 3/4 x .083 chrome moly tubes that are bent, notched, and designed to be welded into the body. The best part about working with S&W is the almost endless combinations the company can build for your project. From an off-the-shelf unit to a completely finished and welded custom bar.

Funkhouser Race Cars installation was meticulous. They really took the time to fit the roll bar exactly as we specified. Remember the kit was modified to retain back seat.

There was one caveat here that presented challenges for the Funkhouser crew. The owner wanted access to the back seat so he can take his two small daughters along for the ride, so S&W provided two clevis and pins to make the harness bar removable, allowing for easy access aft of the front seats.

Access to the rear seat is as easy as pulling the pins and removing the bar. Come race day, re-install.

Many roll ball kits are made for a rear seat delete configuration with the bars plumbed straight through the rear passenger area. Instead, Payback’s main hoop was brought in line with the B-pillar and then the crew at Funkhouser bent the rear bars over the rear seat, through the rear package tray, and welded the rear of the bar to the trunk floor.

Matt Funkhouser tells us, “Accurately measuring the interior, trunk, and roll bar assembly is critical to a precise install. A fifty-year-old car is far from “square” so we use a laser level and test fit everything to make sure were are installing the roll bar as cleanly as possible.  The changes we made to route the roll bar along with the headliner into the trunk took some doing, but we’ve been at the game a long time and our team really pulled it off.”

The bar had to be fitted in the trunk around our mini-tubs. The Funkhouser dudes did a great job.

The Funkhouser crew also welded in a bar at the bottom of the main hoop to provide extra rigidity and also give us a place to mount the lower portion of racing harnesses. The brothers Funkhouser did a very nice install with beautiful welds and precise fitment. The end result is a substantial increase in body structure that will augment handling and offer occupant safety in case of a mishap.

Only the good stuff for Project Payback. Our Lingenfelter tuned, Chevy Performance LT4 looks good in the engine bay of this old A-body.

Next up, keeping Project Payback comfortably cool. With a blown, Lingenfelter-tuned Chevrolet Performance 6.2-liter LT4 crate engine residing between the front wheels, it was time to install a modern radiator to keep things under control. Currently, there isn’t an aftermarket source for a bolt-in radiator for a ’68 GTO running road courses in 100+ degree temperatures, so we had one custom-made by C&R Radiators.

C&R has been in business for decades, providing quality cooling solutions for top U.S. race teams and performance automotive builders. Recently, C&R joined the PWR family of companies, delivering the latest cooling technology for every application.

With a custom application like ours needing a monster cooling system, it comes as no surprise when it’s time to make things fit.

While the radiator was designed to fit perfectly width-wise, we had to fabricate a new “perch” for the radiator to sit on. We utilized the Funkhouser Brothers’ talents here as well. They fabbed up a custom hold-down at the top of the radiator and welded in bar stock where the stock lower support once was. The Funkhouser designed top mounts were sent to the CNC machine for a custom touch, and then outfitted with slick hardware.

We wanted electric cooling fans for efficiency and to eliminate unnecessary parasitic draw on our mighty LT4, so we called fan gurus SPAL, and added a pair of their sweet little twirlers to the backside of the radiator to pull air through.

SPAL is our go-to when it comes to electric fans.

The heat exchanger (for the supercharger) will be mounted in front of the radiator. Eventually, there will be an A/C condenser there that mounts in front of the heat exchanger and mounts a third fan to push air through the heat exchanger. The Funkhouser dudes left plenty of room for all of the gear to live later on down the road.

We thought the GTO logo on the upper radiator bracket was a nice touch.

Lastly, just as we wanted Project Payback to be cool, calm, and collected, we wanted to deliver the biggest, purest hit of oxygen to the engine. The Funkhouser team bent a custom 3.5-inch intake tube to draw air into the throttle body, routing through where the factory battery placement used to be. The battery’s final resting place will be moved to the trunk. The team bead rolled the ends to grab a silicone coupler where we will later install a very large filter so as not to restrict airflow into the LPE-tuned LT4.
All these mods are critical for a smooth-running Pro-Touring rig that will see track time. While not as exotic as other aspects of a build, they are crucial to a reliable machine. A big shout out to Funkhouser Race Cars, S&W, C&R, and SPAL for all their expertise as well. Stay tuned to Street Muscle for all the latest updates to our 1968 Pontiac GTO, aka Project Payback.

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Dave Cruikshank

Dave Cruikshank is a lifelong car enthusiast and an editor at Power Automedia. He digs all flavors of automobiles, from classic cars to modern EVs. Dave loves music, design, tech, current events, and fitness.
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