Feature VehicleNews

What it Takes to Race 4800 Legends at King of the Hammers

In Ultra4, there are several racing classes, and if you want to race at the top level amongst the top drivers, you will go race in the unlimited 4400 class, in which there are essentially no rules besides safety standards. This is the class that started it all at King of the Hammers, but as the years went on and the race cars that had been built in 2007 might not be competitive anymore. So, where do they fit in? They are too modified to race in a limited class and no longer as competitive in the 4400 class. In 2014, the Legends 4800 class was born and since then has become one of the most competitive classes in Ultra4. We wanted to see what a competitive 4800 Legends car was all about, so we had the chance to meet up with Greg Neff at King of the Hammers and learn more about it.

Greg is an engineer by trade and has experience in fabrication, running a shop in Colorado throughout the years. But it wasn’t until his first King of the Hammers in 2013 when he was only a co-driver and he was hooked on the sport. For several more years, he kept coming back and knew he wanted to race his own car. By 2017 he built a race car to compete in the Ultra4 4800 Legends class. Drawing inspiration from a few race cars and other rock crawlers he had built throughout the years, he developed his design.

The 4800 Legends class has a few more rules compared to the unlimited 4400 class. All cars must have a front-mounted engine, solid axles, two passengers, a 37″ tire, and a single shock per corner.

Greg’s 4800 car is powered by a GM LS3 crate engine sending 525 horsepower out through a 6L90 six-speed transmission with tap shift to help spin the 37 inch Nitto tires. This power plant can reach speeds up to 108 MPH on a dry lake bed.

Equipped with a three-speed Hero Transfer Case, Greg can run in the 1.7 mid-range gear and run most of the race in that gear but throw into the 3.7 low gear for the insane rock obstacles like Jackhammer or Outerlimits.

Upfront is a Dana 60 axle, with 35 spline shafts throughout the front with Nitro Excalibur joints and 4340 Chromoly axles shafts. A complete hydro steering system with a TJM locker and 4:88 gears. In the rear is a Ford 9 inch rear, with 40 spline axles and a spooled differential.

Since 4800 only allows for a single shock on each corner, Greg opted for Fox 3.0 Internal Bypass Shocks. The rear is a 14″ shock with 20″ wheel travel, and the front is a 14″ shock with 17.5″ wheel travel. Both are in a straight line measurement, not a flex scenario which would generate higher numbers but not necessarily applicable to usable wheel travel at speed. Still reasonable wheel travel numbers regardless of rocks or desert.

To survive King of the Hammers, you will need a lot of spare parts because it is a no chase race. This means if you break while somewhere on the course, your team can’t bring you spare parts. The driver or co-driver will have to run into the nearest pit, which could even be miles away, grab that spare part and run back and repair it yourself.

With rules like this, Greg tries to carry as many spare parts and tools as possible in any mechanical trouble. Even a mini saw. Why a mini saw? A few years ago, he damaged a bolt in part of the rear axle and needed it cut out so he could put a new one in. Greg spent two hours in the desert with a rock filing the bolt to get it free when the repair could have taken five minutes with the hacksaw. He learned a valuable lesson that day – always carry a hacksaw.

Race day, Greg would line up for the 4Wheel Parts Everyman Challenge with 38 other 4800 Legends racecars and finish the day in 24th overall. While finishing the race itself is considered a victory in itself. An undeniable feat regardless of what class you are racing at King of the Hammers, it is the most challenging race in a single day. We can’t wait to see how he stacks up at the next Ultra4 race.

Chassis: Greg Neff Motorsports Custom Built
Engine: GM LS3 525hp
Transmission:  6l90 Six-Speed Tap Shift
Fuel Cell: 38-gallon fuel cell 
Transfer case: Hero Three Speed
Tires: NITTO 37×12.50-17
Wheels: Raceline Monster Beadlock Wheels
Front Suspension: Fox 3.0 ITB 14″ Shock 17.5 wheel travel 
Rear Suspension: Fox 3.0 ITB 14″ Shock 20″ wheel travel
Front Axle: Dana 60 35 spline TJM Air Locker
Rear Axle: Ford 9″ 40 Spline Spooled
Gearing: 4:88 
Steering: PSC Hydro 
Seats: PRP Seats
Navigation: Lowrance GPS

Bonus Images:


New Member
Mar 1, 2022
RDC Crypto
Love the technical approach as you mentioned. This is the level of detail most of us like to see in these features.


Well-Known Member
Oct 5, 2014
RDC Crypto
United States
We might need to do more Ultra4 features. What do you think @tedlivingston
Please! One of the coolest things about Ultra4 (specifically 4400) is the utter lack of rules. It's one of the few unlimited racing disciplines that is truly unlimited, and has a race course that is so varied that it allows people to get creative so everything is different. Solid axle, ifs, 40s, 47s, rear steer, irs, V8, turbo, everything is different and how it's executed is different. Just the changes year to year that Healy and Horschel bring to the sport is so cool and unique and no one covers any of it.