The Story of Challenger IV, By Rory Ward
It was mid to late 1977 when Mickey Thompson (MT) decided it was time to build yet another new race car for the desert. I’m speculating that he was not too happy with the performance of his single seat “Marines” sponsored class 1 buggy so he and chief Mechanic John House set out to build Challenger IV.
MT was never one to follow in the footsteps of others and building a “Traditional” class 1 buggy was out of the question. Back in those days, single seat VW powered buggies were winning pretty much everything in the world of off road racing. The VW type trailing arm suspension front and rear seemed to be the hot ticket but was limited on horsepower and wheel travel. MT believed that a V8 powered buggy with an A-Arm front suspension and a live axle rear was the way to go.
Mickey Thompson Challeger IV at the 1978 Mexicali 300, Photo by Roger Caddell
The race shop was busy as the Thompson crew of John House, Danny Thompson and Bruce Parrish began fabricating Challenger IV (CH4). Many long nights were spent trying to get the new vehicle done for the 1978 season which started in the border town of Mexicali on the Baja Peninsula. CH4 was fresh out of the race shop with barely any test time, not even enough time to have paint applied to the beautiful hand fabricated aluminum body built by Nye Frank as it rolled into Mexicali that cold February day.
CH4 was a site to see, huge tires, monster V8 and loads of wheel travel, it was the talk of contingency the day before the race and towered over its competition. On race day, MT and son Danny would split the driving. Right out of the box it was fast, VERY FAST. John House had told MT to keep it under 4000 RPM’s because he wasn’t sure about the driveline set up and didn’t have ample time to fine tune it to his liking. Leading the race through checkpoint 4, MT couldn’t seem to keep his heavy right foot off of the skinny pedal and it snapped the driveline sending the racer head over heels across the desert floor. Although the crash was disappointing, MT was smiling because he knew this racer was fast and his competition had no idea what they were in for.
Mickey Thompson – Challenger IV, Photo by Bruce Parrish
Back at the race shop, the crew was busy repairing CH4, they decided that the wheel base was a little short at 104” so they stretched it to 112”. The reason was MT stated that on the HWY sections CH4 was reaching speeds of 150mph and it was very unstable. House and the rest of the crew finished stretching the chassis as Nye built another “duckbill” type wing over the driver’s compartment to help with the aerodynamics at high speeds. One of the biggest changes came in the rear suspension. Originally the rear was set up with 2 Nitrogen filled MT custom coilover shocks mounted in a “V” shape on top of the live axle. MT must not have been happy with the performance so he added a massive 41” long shock so the rear had 3 shocks per wheel.
The 1978 MINT 400 was the first race for CH4 in the states and this time it was race ready with test time and some fresh paint. CH4 was a hit on Fremont Street for contingency and technical inspection, the crowds could not believe how big the racer was. Your typical class 1 buggy had approx 10” of front wheel travel and 12” in the rear. Horsepower was most likely in the 180 to 200 range and a top speed of maybe 100mph. CH4 was boasting 15” of front wheel travel and approx 18” in the rear. The V8 motor was salvaged out of one of MT‘s old Indy cars and de-tuned to around 700HP with a top speed of over 150mph. While they ran 29” front tires and 33” rears, CH4 was running 33’s in the front and 36’s in the rear.
Mickey Thompson – Challeger IV, Photo by Bruce Parrish
On race day, CH4 didn’t disappoint. After lap 1 MT had a 10 minute lead over the next vehicle. The next lap he was able to stretch his lead even more, that after spending a little more time then he wanted to in the pits so they could cool down the motor. On lap 3 Danny Thompson would get in with a 40 minute lead only to be taken out of the race after hitting a slower moving vehicle in the blinding dust. This would be the 2nd race in a row that CH4 was leading with a chance to win but was sidelined with a DNF (Did Not Finish).
Over the next couple years, DNF’s would be the story of CH4. It was always something, leading the race and some small part would put them out. The 1979 Parker 400 was the closest CH4 ever got to a win. While leading 8 miles to the finish the motor just quit. MT got a tow to within a ¼ of the finish line and tried to restart it but it wouldn’t work. Frantic, he ran to the finish line and asked what he could do. He was told if he could push it across the finish line it was legal, but only banded drivers were allowed to push, no help from the outside, including the crew. MT pushed the 2900lb racer across the finish line, exhausted, his legs like jello, but ecstatic that he had finally WON a race.
But It wasn’t to be, the rules state that your vehicle must be under its own power over the finish line (running), and while towing of a vehicle a short distance is legal, it’s illegal to tow within 1 mile of the finish line. MT was not happy, but since it HE wrote the rules 5 years earlier for SCORE, turns out he could only be angry with himself.
1980 would be the last year for CH4, his luck couldn’t have been worse with CH4, although it showed much promise he couldn’t seem to get it to the finish line. He began working on Challenger V, which was basically the same as CH4 (V8, live axle, big shocks/tires) but was wider, longer and was a mid engine. The 1980 MINT 400 was the final race for CH4, it was then parked at the back of the shop with the rest of his old race cars and stayed there till his untimely death in 1988 when he and his lovey wife Trudy were murdered on his front driveway.
MT’s son Danny and Daughter Lyndy would take possession of his old race cars as half went to Danny’s race shop and the other half to Lyndy’s place in Oregon. CH4 would sit in a loft for the next 18 years until a phone call from a curious Off Road racing fan would HOPEFULLY change its fate…………
The picture that started it all for Rory Ward’s Mickey Thompson Challenger IV restoration project