By the staff of Dirt Wheels

*A Build of an Assault Industries UTV know as “P51”.

This long and ultra-fast sand wash near Barstow, California, is only medium rough and choppy. We could hit it flat out.


So many companies build truly amazing machines for the annual Sand Sports Super Show that it is difficult to come up with a combination that literally stands out in a massive crowd. As builders of many impressive machines, Assault Industries knows that standing out in such a crowd takes an over-the-top effort, thus their newest Assault Vehicle.

Assault Ind. was up to the task. We spotted the Polaris RZR XP 4 Turbo S project from 100 yards off as we walked the lanes of the Sand Show. Assault faced a further obstacle in coming up with a stunner; they started with a car that is largely black. That color doesn’t exactly shine in the sun.

The answer was in the Assault catalog—the Tank door kit. Of course, those are black. Assault fixed that problem by chroming all four of the Tank half doors. Combining the many square feet of chrome steel doors with custom Assault graphics was the perfect way to make the black Polaris stand out in a crowd.

We knew that the 35-inch tires would help rollover ledges and obstacles, but we expected gearing issues that did not surface.



Despite having more actual chrome than 99.9 percent of all sport UTVs, this Assault RZR 4 Turbo S called the “P51” is far from a show queen. Up top is a Cage WRX super-shorty cage. It is available in three ways, and the most complete is fully assembled and powder-coated with an integrated roof. Attached to the silver-gray cage are an Assault fire extinguisher mount, front and rear 30-inch Baja Designs light bars, and some pod lights, whip mounts, mirrors, and an S&B Particle Separator.

In addition, there are a variety of Assault convenience items like sun visors and other details. While not really part of the cage, Assault has a truly awesome Adventure rack that mounts over the bed. It pops up on gas struts with just a lever. It can support all sorts of gear or even a spare tire. When the rack is dropped, it fits close enough over the bed that you don’t even need to tie lightweight items down in the bed area.

The Simpson seat colors complement the look of the car. The Tank door kit mounts to the stock quarter-door inner structure.


Starting at the bottom, the team chose an HCR Dual-Sport OEM replacement suspension kit that uses the stock geometry and mounting. It came in raw metal, so Assault ordered it raw, then made it bright and shiny with chrome-like doors. The Turbo S came stock with 32-inch tires that were stunning when they were released, but Assault jumped to 15-inch Method Beadlock wheels with monster 35-inch Tensor tires. Nothing about these monster tires looks out of place. It looks ready to rumble.

Small changes, like plenty of mirrors, music, an intercom, sun visors, and such, make such a difference in a long driving day.



Four Simpson Pro Sports seats combine safety, comfort, and style, and they mount to the stock Polaris quick-release seat bases. Add quality Simpson harness-type seat belts and you have a great package. The race seats and the Rugged Radios-supplied helmet air system, car-to-car radio, and an intercom to connect the driver and passenger are quite nice in a trail machine.

In addition to the seats and the electronic gear, Assault went with its 350R steering wheel and steering wheel hub, then added fun items like a grenade shifter and a billet passenger grab bar.


Seeing no reason to go crazy with the power, Assault added an exhaust, an ECU tune, and a few other parts from Evolution Powersports to enhance the performance. A stock Turbo S is a heavy machine, and there is no doubt this one is heavier. Performance remains astonishing even with the 35-inch tires! The engine mods let the engine produce all the power possible without hurting reliability.

This Turbo S literally looks like it is on the hunt! This is a serious build that easily justifies every change made.



We have a lot of time in an XP 4 Turbo S, and with the Dynamix suspension, it is an amazing machine with great performance and stunning ride quality. While we rarely filled all four seats, but it was our go-to car for as long as it was in our stable. That got us to thinking that it didn’t need much in the way of modification. Then after driving the Assault P51, we are questioning our thinking.

You do sacrifice a little cab room for the generously padded and bolstered Simpson seats, but they are superbly comfortable, and the Simpson belts are easy to adjust, comfortable, and impart the same feeling of safety as the stock harnesses.

We had a Rugged Radios intercom system in our Turbo S, and it makes rides with other people 300 percent more fun and interesting. And, if you drive at night, the Baja Designs light bars and lights bring the whole world to life. Quality lights and light placement make that large of a difference. In some ways, you can relax a little driving at night. It is easy to see if other machines are coming.

Assault’s RZR Turbo S project is built to roll fast. Pour on the throttle and it just loves it when the scenery is blurred.


This was the first time we ran 35-inch tires. We feared that the already somewhat tall stock low-range gearing would suffer even more in slow and technical driving. To our surprise, it worked great on steep and rocky climbs with no sign of belt abuse. In the slow, technical sections with rocks and ledges, the tires let the car roll easily over obstacles.

For full-throttle, high-speed running, the P51 exhibited great manners. It feels safe and stable at speeds that boggle the mind.

We are in love with this pop-up adventure rack over the bed area. It constrains soft bags underneath, plus carries a spare on top.


Forward vision is great, and we even found ourselves appreciating and using the flip-down sun visors climbing rock trails right into the sun.

Assault chose well when it came to what equipment should be added and what stock parts deserved to remain in place. The build was aimed at all-day, high-performance trail comfort.

Assault’s bumper and massive billet radius rods help to bulletproof and protect the rear of the car.



Too many project cars feel like they add parts just to put them on, but the P51 didn’t feel like it had anything that was not needed. Sure, some of the parts were just for looks, but the vast majority have a positive effect on safety, comfort, convenience, or performance. It makes us miss our Turbo S even more.

By the time we drove the car, parts of the wrap needed a little refreshing, but otherwise the car has held up well and felt strong.



ASSAULT INDUSTRIES: (714) 799-6711, www.assaultind.com

Adventure rack $479.99

Turret radius rods $519.99

Turret tie rods $329.99

Front/ rear sway bar links $124.99 ea.

F.E. quick-release kit $169.99

Tank door kit $529.99

3” H-style harnesases $139.99 ea.

Front shock guards $124.99

Phantom convex side mirrors $309.99

Bomber convex rear-view mirror $99.99

Ghost tinted sun visors $169.99

Grenade shifter $59.99

Turbo S grill $149.99

350R leather steering wheel $169.99

Steering wheel adapter hub $64.99

Steering wheel quick-release hub $124.99

Fire extinguisher kit $169.99

Spare belt holder: TBA

BAJA DESIGNS: (800) 422-5292, www.bajadesigns.com

30” Onx6 LED light bar kit $1,149.95

XL Pro, pair driving/combo, 

   amber $699.95

RTL-B 30” light bar $424.95

LP9 Pro LED $599.95 ea.

BUGGY WHIPS, INC: www.buggywhip.com

4’ LED quick release whips $149.99 ea.

CAGE WRX: (951) 223-9118, www.cagewrx.com

Super-shorty roll cage, assembled, powder coated w/roof $2,499

EVOLUTION POWERSPORTS: (715) 247-3862, evopowersports.com

Magnum exhaust $699-$999

ECU programing $499-$699

V-flow intake boot $169

Silicone charge tube $169

HCR RACING: (888) 928-7223, www.hcrracing.com

Dual-Sport OEM replacement suspension kit $3,499.99

K&N FILTERS: (800) 858-3333, www.knfilters.com

Performance air intake $349.99

METHOD RACE WHEELS: (866) 779-8604, www.methodracewheels.com

401-R UTV beadlock low offset $299.99 ea.

PROLINE WRAPS: (818) 348-3120, www.prolinewraps.com

Vehicle wrap Varies

ROCKFORD FOSGATE: (800) 669-9899, www.rockfordfosgate.com

RZR 14 RC Stage 5 kit $2899.99

RUGGED RADIOS: (888) 541-7223, www.ruggedradios.com

2-person pumper system $556

RM50 50-watt remote head dual band radio $399

660 plus intercom $599.99

S&B FILTERS: (800) 358-2639, www.sbfilters.com

Particle separator $399.99

SIMPSON RACE PRODUCTS: (800) 654-7223, www.simpsonraceproducts.com

Pro Sport seats $549.95 ea.

SXS INDUSTRIES: (714) 821-1377, www.sxsindustries.com

Wiring & sound system install Varies

TENSOR TIRE: www.tensortire.com

DSR 35-inch $399.50 ea.

XTC POWER PRODUCTS: (480) 558-8588, www.xtcpowerproducts.com

Plug & play 4-switch control system $329.99

Plug & play turn signal system $339.99

Factory replacement rocker covers $29.95

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