This is the Proving Grounds Racing # 4570 truck that competes in the 4500 class in this year’s King of the Hammer off-road race. It is based on the Jeep Wrangler Unlimited TJ / LJ chassis. (Picture /Proving Grounds’ Facebook Page)

The 2021 edition of King of the Hammer has been running for about a week in Johnson Valley, California. The annual competition lasts several days, and this Saturday culminates in the main event: a challenging 90-mile cross-country race that combines high-speed desert running with precise, technical rock climbing.

This year’s contestants include veteran off-road racer John Grounds and Field Race Proof team. The team consists of skilled technicians, vehicle manufacturers, and off-road racers. King of Hammers and similar events – plenty of podium finishes in the process. The team drives a pair of vehicles in this year’s competition.

Let’s take a quick look at the trucks and get a better understanding of the King of Hammers event.

For starters there is several different vehicle classes Competing in the King of Hammers. As mentioned above, Proving Grounds has prepared two vehicles for 2021: one in the 4400 class and the other in the 4500 class.

4500 Modified Class means the vehicle must use a modified OEM or OEM style chassis and have mechanical steering. These trucks must use a pair of 2.5 ″ diameter shocks at each corner and 37 DOT approved tires.

4400 Ultra4 Unlimited Class grandfather of all. These trucks must use a 4-wheel drive transfer case and meet a strict safety standards checklist. Apart from that, pretty much everything else applies: there are no limits to the chassis / chassis, tire size, engine type, axle or suspension design.

Proving Grounds Racing off-road vehicles 4570 and 4415 as well as a Jeep Wrangler support vehicle. (Image / Proving Grounds’ Facebook Page)

Proving Grounds’ 4500 series truck, number 4570, is based on the Jeep Wrangler Unlimited TJ / LJ. The 4400 series truck The 4415 has a custom built Miller Pro Chassis where you can watch it come together. 4415 is here on progress page.

The 4415 was built almost from scratch. The chassis is assembled from a kit that is welded together, and all plumbing and electrical work is custom installed. And while the 4415 has a large number of one-off custom made components, the truck has also been given some familiar names. Wilwood Brakes, BFGoodrich tires, and Fox Racing Shox Shocks.

The team has been in Johnson Valley, California for over a week, testing, adjusting and pre-running the course. Long days and short nights are normal. (Image / Proving Grounds’ Facebook Page)

It’s really fun to watch if you’re new to this type of off-road racing. And you can get an idea of ​​how exciting it is just by looking at the vehicles – part rock crawler, part dune buggy, and part stadium truck.

And you can do something cooler Watch King of Hammers events live online on Ultra4 Racing’s website. And you can be updated King of the Hammers race results There too.

Here, Proving Grounds truck # 4415, Chuck crossland4800 class racer # 4869 and twin turbocharged LS engine. (Image / Proving Grounds’ Facebook Page)

And while we’re cheering on Proving Grounds’ efforts, we really do have the support of the whole event and all attendees and attendees. King of the Hammer and related off-road racing is a great category of motorsport that we hope to continue to grow and develop.

The Hammer King’s main race will start at 8:00 AM on Saturday, but be sure to check for date / time updates at this time. official race week schedule From Ultra4 Racing.

Author: Paul Sakalas
Paul is editor of OnAllCylinders. When he’s not writing, you’ll likely find him throwing tools at his unfortunate day-to-day driver or tampering with an old Jeep CJ-5. An ambitious motorcyclist spends the rest of his time synchronizing the carburetors and removing grease from his left trouser leg.