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Riviera Racing: Black Diamond Trophy Truck: A Baja Icon

The year is 2007; the SCORE San Felipe 250 had moved to Ensenada, and Riviera Racing driver Rob MacCachren had spent the first half of the race in the Black Diamond and passed it off to Mark Post to finish the race. The police tried to pull over Mark during the race to ask a question on the highway, but Mark wasn’t stopping unless it was for the finish; the race had now turned into an all-out police chase. Mark had done nothing wrong, and he knew if he pulled over he would lose the race so he kept pushing. With the finish line in sight just 300 yards to go, the race would come to an abrupt end; police had guns drawn, and with nowhere to go they arrested Mark. It turns out there was no specific reason to pull over Mark during the race, so he continued on regardless and the whole thing was a big misunderstanding. The Riviera Racing team would go on to win that race and win the Baja 1000 later that year. But that isn’t where this story begins or ends for this truck; it is just one example of the many stories of legendary drivers who have driven the legendary truck known as “Black Diamond”.

How does a Trophy Truck reach this level of legendary status, and how does a 30-year old truck still remain competitive in Baja today? This story begs the question – is this the best Trophy Truck ever built? This is the story of the legendary Riviera Racing Black Diamond.

The story starts with Robby Gordon a legendary racer in Baja who needs no introduction. In 1993 he had been racing for over 10 years and had been very successful in racing MTEG, Class 1, Class 8, and others and had won the Baja 1000 twice. But he had also just begun his career in CART Indy Car racing, IMSA, and NASCAR. But his passion was always in off-road racing, and he wanted to build something that changed the sport and pushed the boundaries of engineering.

Racing at that level of motorsports, he had access to talented people who also knew a thing about off-road racing. So they got to work with the help of Don Fair, Dave Forbes, and Ed Buffington. By 1994 it was completed for the debut season for the Trophy Truck class in SCORE. Robby wanted to push the boundaries of off-road motorsports technology, so they worked on building the truck utilizing technology that had never been implemented before. Some of those firsts included internal bypass shocks allowing for only one shock per corner, swing set steering, removable rotor hats, and a unique suspension design.

“It took a small group of talented fabricators to build the truck. None of us were engineers, but we were just Imagineers and built it.” – Robby Gordon

By the 1994 season, they hit the ground running for the inaugural season for the Trophy Truck class. With Robby’s Indy sponsor Valvoline across the side of the truck’s body it could be seen racing through deserts at speeds upwards of 130 MPH. His first win in the truck would be later in the year at the SNORE Eldorado 250.

Aerodynamics took a large role in developing the truck to be stable at high speeds. In 1996 the truck body was changed to match the newer generation of F150. Robby commissioned automotive designer Clay Dean to design the fiberglass body. Extensive wind-tunnel testing would optimize drag coefficients; they wanted every possible competitive advantage over the other racers dialing in the air ducting and rear wing for downforce.

By that year, Robby had won six races so far with the truck since initially building it in 1993. He would go on to win the SCORE championship that season as well. He would take a break from off-road racing altogether and not return for the 1997 season to focus on a promising NASCAR career following his piers’ advice. A decision he would later regret.

But Robby still had aspirations for off-road racing; it just took a back seat for a few years and wanted to develop a mid-engine truck. The truck sat in the back of their shop in California, collecting dust from then on, waiting for another day for someone to get behind the wheel and race it.

Mark Post of Riviera Racing had Robby Gordon internal bypass shocks being built for his 4wd Class 1 Buggy. And on the day he picked them up from Robby’s shop he noticed a truck covered in dust in the corner. He asked Robby if he would sell it and the only condition was that the matching prerunner was to go with it. They shook hands, and the deal was done – that dusty truck in the back corner would become one of the most famous trucks in Baja, known to locals as “Diamante Negro” or Black Diamond in English. Robby would later get back to off-road racing and build a mid-engine Trophy Truck truck.

It took the team a few years to learn how to prep and race a Trophy Truck, but with Jim Blackmore coming in as crew chief, they started seeing great success in racing. It wasn’t until 2000 Mark would get his first win in the Black Diamond at the SCORE Primm 300. Mark raced various races throughout the years, winning a few races and earning many podium spots. But the good years were still ahead of them; that year was 2007.

2007 was a transformative year for the Riviera team. Legendary Rob MacCachren joined forces to race on the team with full Rockstar Energy backing; they set their sights on winning. The same year, the police chase incident left them victorious at the San Felipe 250. Two additional wins at Best in the Desert and the Baja 1000 overall win made them champions. This was no small feat; it was one of the longest Baja 1000 races to date – 1296 miles from Ensenada to Cabo. With the recruited help of Carl Renezeder they finished in 25 hours and 12 minutes.

“The harder you drive it, the faster it wants to go,” – Mark Post. 

Mark continues to race the Black Diamond to this day as the oldest Trophy Truck in the race lineup. One could argue that it is still a competitive 2WD truck, and Kyle LeDuc proved that in 2016 by qualifying 1st at the Baja 1000, and the Riviera team led a majority of that race. Mark even won the NORRA 1000 three years in a row up until 2019. But standing back and watching this truck move, you would never guess it was built in 1993. It moves fast and aggressively, stays on top of the bumps and just checks out.

So, what about the truck mechanically does it have that makes it so great? It isn’t just one thing; it is a combination of things put into it that makes it unique. The front J-arm suspension allowed for clearance around the engine or more travel and was good for 24 inches of front travel. It still used the original set of internal bypass shocks Robby designed until 2020 to where they got a new set. The truck has a Patton Small Block sending 850 horsepower to a Turbo 4000 and a Rancho underdrive. Even the small things on this truck made it unique such as the now standardized 6×6.5 hub bolt pattern. Removable rotor hats are all things that have drawn inspiration from other forms of motorsports. As Mark would say, “the truck just works.” For a nearly 30-year-old truck to go reach speeds in excess of 130 mph out in the desert and battle it out with some of the latest and greatest trucks designed in recent years is an impressive feat.

But the most impressive thing about this truck is how unchanged it was from its initial build in 1993. It uses the original suspension design, and most of the chassis remains the same except for a new engine and rear fuel cell. Most trucks this old have been cut apart and rebuilt numerous times to improve it, but the Riviera team felt that the truck was great how it is.

At this year’s Baja 1000 Mark teamed up with some good friends to go race in the legends Trophy Truck class – Ed Herbst and Curt LeDuc. Although they didn’t win, they did finish third in their class. With crazy advances in all-wheel-drive Trophy Trucks, it is hard to remain competitive in a truck with two-wheel-drive. But with the right driver and the right conditions anything is possible. Regardless of a win or not, this truck has a soft spot in everyone’s hearts and is known for being one of the greatest trucks of all time. Win or lose, Mark is still out there enjoying racing and shows no sign of slowing down anytime soon. If you didn’t know how the Black Diamond came to be about, well, now you know.

Bonus Gallery:

 

Specs:

Chassis: Custom Tube Chassis built by Robby Gordon
Weight: 6000lbs
Engine: Patton Small Block Motec Engine Management
Cooling: Rear-mounted radiators and cooling fans
Lights: KC HiLites, Baja Designs
Exhaust: Custom Headers
Transmission: Chevy Turbo 400
Tires: 37×12.5r17 BF Goodrich KR2
Wheels: Ultra Beadlocks
Front Suspension: J-Arms, Robby Gordon Internal bypass shocks coil-overs
Rear Suspension: Four-link, Robby Gordon Internal bypass shocks coil-overs
Navigation: Lowrance GPS
Communication: PCI Race Radios/ Rugged Radios
Seats: Cobra
Safety: Fire suppression system

 

Black Diamond Overall Race Wins: 

1994 SNORE Eldorado 250
1995 SNORE Vegas 300
1996 SCORE Parker 400
1996 SCORE San Felipe 250
1996 SCORE Primm 300
1996 SCORE Fireworks 250
2000 SCORE Primm 300
2002 SCORE Terrible 250
2003 SCORE Laughlin Desert Challenge 
2003 SCORE Terrible 250
2004 SCORE San Felipe 250
2007 SCORE Baja 1000
2007 BITD Terrible Cup 250
2007 BITD Parker 425
2013 NORRA 500
2017 NORRA 1000
2018 NORRA 500
2018 NORRA 1000
2019 NORRA 1000

 

The Police Incident:

NIKAL

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A little correction. The first mid engine TT Robby built was not the current truck he has. He built one previous to this one, which was sold to Marty Coyne. The original mid engine TT wore Toyota, Menards, Turtle Wax and a few other sponsors on it. The current RG truck was never named Unicorn until it was kept under wraps while being converted to a 4wd truck. That’s when the Unicorn name came about.

First mid engine TT that was sold to Coynes.
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Jammminjay

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A little correction. The first mid engine TT Robby built was not the current truck he has. He built one previous to this one, which was sold to Marty Coyne. The original mid engine TT wore Toyota, Menards, Turtle Wax and a few other sponsors on it. The current RG truck was never named Unicorn until it was kept under wraps while being converted to a 4wd truck. That’s when the Unicorn name came about.

First mid engine TT that was sold to Coynes.
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You are totally right I got this part wrong and messed up. Thanks for the correction. :) I fixed it.
 

BajaFand

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Correct on that. I believe Jesse Jones was the last guy to own it before Robby bought it back to convert into a prerunner. It was for sale a couple of months ago, not sure if it sold or not.
 

NIKAL

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The Chet Huffman TT was built side by side with the current RG TT. It was built as a way to help finance RG’s TT. Cheaper to build two of them. Then Chet sold it to McMillin who made some big changes to it. Then Jones’s bought it who then sold it to RG who then converted it into his 4 door mid engine prerun truck.
 
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mig29

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JWK Motorsports:

What about the Chet Huffman TT?

The Chet Huffman TT was built side by side with the current RG TT. It was built as a way to help finance RG’s TT. Cheaper to build two of them. Then Chet sold it to McMillin who made some big changes to it. Then Jones’s bought it who then sold it to RG who then converted it into his 4 door mid engine prerun truck.

I was at CORR '07 Primm, the Geiser's brought the Chet Huffman TT (built by Geiser). Did Huffman have another TT (Geiser built?). I remember Jesse Jones (racing Pro2) in the Geiser booth (they were supporting client racers), I showed him the wreck by John Marking during Pro4 Q'fying:



See pic, Chet Huffman TT at SCORE '06 Terribles Cup, Trophy Truck Friday Heat #2. Jump at Start/Finish

You can barely make out the bottom A-arm ("fattish"), looks like the one on Mark Post's TT #3
 

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mig29

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Rob Mac and this truck together were an amazing combination. This truck is an icon.

I remember the 2007 Primm 300 near Knight Ranch Road, Rob came in on the last lap -- ON FIRE! He was doing his patented:

"I drive slow enough to WIN"

I.e., taking a conservative approach early, getting splits from team, & going for it at last lap


The drivers before RobMac were Jerry Welchel & Curt Leduc. I remember seeing Jerry & TT #3 at Ojos Negros (2003 Baja 1000?), Jerry was driving the Semi taking the broken TT#3 back to Ensenada. He asked me if I got some good pics. Previously, I ran into Mark Post (& his Dad?) at a pit off Hwy 3

Dad: Jerry's stuck (at Mikes')
Mark: That's easy to do
[ while eating a sandwich ]

Jerry had a DUI, so that's when Curt took over, 2005? I remember seeing Curt at end of SCORE '05 Pri 300, he was checking out the printed results:

"I had a bad day!"

RobMac was driving for Vildosola Racing in 2005 (SCORE & BITD), with Nye Frank on the team. Vildosola Racing was tapping into the "braintrust & racecraft:

RobMac (driver) & Nye Frank (builder)

Once RobMac got in as driver (2007?), the TT #3 "came alive" -- Driver is IMPORTANT!

Driving is a mental game, not just physical. See pic, quote by Olympic cyclist Alexei Grewal. Found at a Specialized bike shop in OC (Orange County)
 

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Curtis Guise

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I was at CORR '07 Primm, the Geiser's brought the Chet Huffman TT (built by Geiser). Did Huffman have another TT (Geiser built?). I remember Jesse Jones (racing Pro2) in the Geiser booth (they were supporting client racers), I showed him the wreck by John Marking during Pro4 Q'fying:



See pic, Chet Huffman TT at SCORE '06 Terribles Cup, Trophy Truck Friday Heat #2. Jump at Start/Finish

You can barely make out the bottom A-arm ("fattish"), looks like the one on Mark Post's TT #3

Chet Huffman bought John Marking's class 1 and put a truck body on it at some point. That might be the one in your photo.

This is from an offroad.com article when he raced the class 1 at the 2007 Terribles Cup.
t_cup_pre_2_07.JPG