Cut Gem: Chris Hamerslagh’s 1969 Opel GT Crawler

Creation is one of the greatest feats of the human mind. Every day, we can think of a new idea and either dismiss it or carry it out. Fortunately, Chris Hamerslagh went with the latter, and applied it to his 1969 Opel GT.

We met Chris at the 2020 King of the Hammers, back before the world went into shutdown mode. You might remember that time. Anyway, the day we met Chris was during the Saturday following the big race, as King of the Motos was raging. Just outside of Backdoor, Chris’ GT was parked next to the deep canyon.

After staring at the car for a good few minutes, we got down to brass tacks and quizzed Chris on his unique machine. What we learned was that Chris kind of has a thing for GTs, and when he gets an idea, it’s hard to stop it.

Background Of The Build

“I’ve always been a devoted follower of Opel GTs,” said Chris. “I’ve wanted one since I was in high school. Nowadays, I have five of these things. On this one, I just brought it into the shop and started to make a 4×4 out of it. It got a little out of hand!”

Chris started working on this dark red GT in 2002. The inception for the idea came from Chris’ friends. “I worked with guys that had these Toyota ‘truggies,'” explained Chris. “These were buggies and trucks mashed into one machine. I was already a huge Opel GT fan by that time. So I took an ’85 Toyota SR5 frame and got to work.”

For the body, Chris secured one from a 1969 Opel GT left neglected on a front lawn. “It’d been sitting around for about four years,” commented Chris. “It was so bad, there was grass growing through the hood. I kept it for a number of years.”

16 years is a long time to devote to one project, but the effort was well justified. “I took my time with it,” commented Chris.

If there’s one thing you can’t say about Chris’ GT, it’s that it happened overnight. “It took me about seven years to get it where it is now,” he said. “I was working on it here and there. On hot days out in Fresno, California, it gets to 120 degrees Fahrenheit, so I wouldn’t dare touch it. About four years ago, I started testing and tuning it. And two years ago, it was ready for Moab, so I took it out there for the first time. Now, it’s a regular thing, we go out there and do about 10 trail rides a year.”

Carving Opel

One of the first things to do was figure out how to put a German car body atop a Japanese truck frame. Needless to say, some surgery was required. “The truck frame came in at over 15 feet long,” said Chris. “The truggies I saw all had triangulated four-link axles front and rear, and they were pretty short overall. I bought a couple of kits from Trail Gear and figured out that I needed to cut out six feet of the frame on the rear, and two up front.”

Chris wanted to keep the original Toyota drivetrain – a 22R-E and five-speed manual transmission – but the GT body wouldn’t allow it. “I wound up moving the body back two feet and down two inches past the top of the frame,” he said. “After I relocated the front crossmember, the body, frame, and drivetrain were all happy with each other. All told, I kept about 7-8 feet of the original Toyota frame. Half of what it originally was.”

Chris now had a rolling chassis, but it wasn’t to the point of rock-crawler extraordinaire just yet. To get to that point, Chris had to take care of the suspension, brakes, tires, wheels, and other necessities.

Highlights Of The Build

Chris took no shortcuts when it came to the GT’s suspension. “I triangulated the front and rear, and put on prototype 24-inch FOX shocks,” he said. “I tuned the shocks to have more oil and run with a little more pressure than normal. Thanks to my setup, the GT gets about 17 inches of down travel and 7 inches of up travel. I use limit straps to keep it from coming apart, too.”

On the drivetrain, Chris used Trail Gear Rock Assault one-ton axles front and rear. He installed Trail Gear Six Shooter steering knuckles on the front axle, capable of turning the wide and heavy tires. In the case of this rig, those happen to be 39.5-inch IROK Super Swampers with custom-made 15-inch beadlock wheels. The rearend was a stock Toyota unit, built up with an ARB air locker and steel truss, all the better for improving grip and overall durability.

The upgraded 22R-E four-cylinder engine puts out 160 horsepower, powering stout axles with ARB air lockers and 39.5-inch IROK Super Swamper tires.

For the engine, Chris retained the original Toyota 22R-E. “I gave the engine a lot of work,” he said. “I gave it a new head, bigger injectors, and a Rock Ripper header, among other things. It puts out about 160 horsepower, and for a car that weighs 1,700 pounds, that ain’t bad.”

The transmission was upgraded to a beefier Marlin Crawler five-speed manual transmission, and the transfer case was upgraded to become a doubler with low-end gearing. A set of shifters control the Trail Gear Trail-Creeper dual transfer case, and can easily employ low-end gearing with the shifters to crawl up any obstacle he comes across. “On compound low and on the rev limiter, I can walk faster than it goes,” said Chris. “It’s like 100 yards per hour. Just really slow. I doubt I’ll ever have to use it, but if I do, it’s there.”

The GT's interior featured the original Toyota dashboard, modified to fit into the GT's cabin. Chris had safe and secure seats and harnesses, shifters for the doubled transfer case, and a switch panel to power ARB air compressors.

For the cage, Chris manned up and crafted his own out of 1.75-inch DOM tubing he bought for himself. “I designed it in a way that it can be unbolted and taken off,” he said. “That way, if the fuel pump goes bad or something, I can unbolt the nearest section and get to it pretty easily. I used my own manual bender and muscles for this cage, no hydraulic benders or anything.”

Inside the car, Chris and a passenger sit in a pair of Smittybilt XRC seats with Corbeau harnesses. A switch panel lets Chris activate a pair of ARB air compressors, which in turn activate air lockers front and rear, or allow him to reinflate the tires after a trail ride.

For the dashboard, Chris reused the one from the Toyota and reshaped it to fit the slimmer space of the GT. “All it took was some new brackets, and it bolted in,” he said. “As for the pedal assembly, same thing. I just massaged it in and welded it into place.”

Another interesting feature of the vehicle was Chris' pop-out windows. Using vel-cro and plexiglass, Chris managed to craft windows that attach and detach at the drop of a hat. It's useful for when he wants access to tools or supplies. And yes, that is a welder mounted inside the cab.

Sports Car Looks, Tough Truck Guts

Taking it all in, it was clear that Chris made decisions about how to build the GT based on the Toyota architecture. “I didn’t get rid of the old SR5 body for a long time,” he commented. “It was only after I had taken everything out of it that I wanted and my wife said I had to get rid of it. So I just cut it up into pieces, took it to the junkyard, and sold it for scrap.”

Chris was quite pleased with where the GT was at when we met him at KOH, but he wanted to do some more work to it in the future. “I like doing front digs,” he said. “So I think I’ll figure out a rear driveline disconnect so I can do front digs.”

Looking back on the project as a whole, Chris is pleased with the result and proud of the work that went into it. "Building this project was more than half the fun of owning it," he said. "It really expanded my mechanical abilities."

It’s a trusty machine and has served Chris well up until now, but Chris knows that there may be room for improvement. He confessed that the GT only has about 1,000 miles on it since he wrapped it up in 2018. “I haven’t found a failure point yet,” he said. “But it’s still a ton of fun for weekend trips and coming out to events.”

With its hefty exterior cage, reliable motor, and heavy-duty drivetrain, Chris’ 4×4 Opel GT has the capacity to keep on running for a long time to come. We look forward to seeing it again once things are back to normal and off-road events are back on the menu.

About the author

David Chick

David Chick comes to us ready for adventure. With passions that span clean and fast Corvettes all the way to down and dirty off-road vehicles (just ask him about his dream Jurassic Park Explorer), David's eclectic tastes lend well to his multiple automotive writing passions.
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