Will This LS-Powered 1970 Challenger Anger The Mopar Faithful ?

Cris Gonzalez' Challenger is Plum Crazy Purple, but it might have Mopar lovers seeing red.

Cris Gonzalez, owner and operator of JCG Restoration & Customs (JCGRestorationandCustoms.com) in Oxnard, California, has built some of the baddest Pro Touring cars around, including the Blu Balz Camaro, an over-the-top muscle car that left Italian supercars in its wake. Cris’ latest project, a 1970 Dodge Challenger, moves down the color spectrum from blue to purple, but it might have Mopar lovers seeing red.

Fabrication, suspension, and mechanics—Cris is good at everything, except Mopar engines. Under the hood of the Challenger is a Mast Motorsports LS3. “I get a lot of disappointment at the track when they find out it has an LS engine, but then they’re amazed at how fast it is,” Cris said. People tend to forgive a lot for the sake of more horsepower.

2/58 The team built the car to the proper ride height, mounted the wheels without fenders, and then custom-built fenders around the wheels. The widened sheetmetal houses huge Forgeline ZX3 wheels: 19x11s in the front and 19x12s in the rear.

The LS in the Dodge makes 605 hp to the flywheel at 6,500 rpm along with 540 lb-ft at 5,500 rpm. The big challenge is putting that power to the ground, even with 12-inch-wide tires. “We’ve pretty much found [their limit],” Cris said. “It grips so hard in the front, we don’t have many issues. Now it’s about playing around with [the rear] springs. When we get some springs, we can get some forward launch.” A Holley EFI Hi-Ram intake (installed after our photo shoot) moved the torque curve higher into the rpm range and made the car manageable on the bottom end while exiting corners. “I don’t have the torque trying to spin my tires [now],” Cris said. “On the road course, rolling through a couple esses, I want to be able to roll on the throttle and not get sideways.”

3/58 No, it’s not a Mopar, but the power and ease of parts acquisition make up for the lack of brand loyalty. The Mast Motorsports LS3 aluminum block has a 4.070-inch bore and 4-inch stroke, resulting in 416 ci. Callies forged crank and H-beam rods round out the bottom end with 11.2:1 compression.

4/58 Kooks stainless-steel longtube headers let the LS3 breathe into 3-inch Borla and custom X-pipe.

How did Cris end up building an LS-powered, road-race Challenger in the first place? He teamed up with long-time friend and owner of Blu Balz, Karl Dunn, with the goal of building a car specifically for the Ultimate Street Car Invitational. Karl had been competing in Optima events with a 2007 Saleen Mustang. If you’re a Ford guy and weren’t offended by an LS-powered Mopar, you may not want to know where the LS was before the Challenger: Karl’s Saleen. When a customer of JCG expressed interest in the Mustang, Cris put the original drivetrain back in the Saleen and traded the Ford for the Challenger. Then, since he had the LS ready to go, it went right in the Dodge.

5/58 Sparco racing seats hold Cris and passenger in place. A complete Safecraft fire-suppression system, when pulled, can douse flames under the hood, interior, and trunk simultaneously. JCG built the four-point rollcage.

6/58 Speedhut gauges handle rpm and speedometer duty while an American Autowire system takes care of the wiring. The car uses a complete AIM Sports data-acquisition system to report back from the track.

The Challenger was a 10-year-old restoration with decent paint and a straight body. JCG built the suspension basing it on Blu Balz’ C6 front clip. JCG builds a C6 spindle of its own design and assembles them in a jig. Cris worked with JRI (JRIshocks.com) to produce a special set of JRI/JCG coilovers with Eibach springs for the Challenger. The only part on the front suspension not built in-house are the Speedway Engineering sway bars. It took the team only 10 months to finish the complete build.

Operated by the Ultimate Street Car Association, the Challenge is a two-day event where street-legal cars are put to the test with a poker run, speed-stop challenge, style judging, and road-course race. Entries collect points on how well they do at each challenge. The Challenger haswon the Lingenfelter Performance Engineering Design and Engineering award while chasing overall class points for the series. Lightened to 3,350 pounds, the car is designed for a road course, so for the autocross Cris removes the rear swing arm so the Challenger can transition weight faster for tight back-and-forth turns. On the road course, however, the car needs to be stiff. “We don’t want a big ol’ sloppy car,” Cris said. “Right now, we’re dealing with a four-wheel drift.”

At the Optima event in Daytona, the LS starved for oil on the long, steep banks. Currently, the engine is awaiting its return after fixing a spun bearing. For the last couple races, a Chevrolet Performance 525hp LS3 crate engine has filled in. It’s down by 80 hp compared to the Mast Motorsports mill, but that engine will return to the car for future races.

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Watch It!

Search user name “JCG Customs” on YouTube for videos of the Challenger on the track with on-screen vehicle speed and engine rpm.

8/58 JCG and a group of autocross friends who drive Miatas and Corvettes rent out the local airfield and set up a different autocross track at least once a month. It’s a racer’s dream, plus it doubles as a test bed for new parts.

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