Polaris UTV Product Reviews

Polaris RZR 800 Holz Stage III Engine Kit Review

Polaris RZRHolz Racing Products
Stage III Engine Kit Review

Holz Racing Products Stage III Engine Kit for the Polaris RZR

Holz Racing Products Stage III Engine Kit


Like many other off-roaders, I am always on the hunt for more power. But there is a little bit of a difference when it came to my Polaris RZR.  I use my Polaris RZR in a wide variety of terrains and at different altitudes.  Anything from the Imperial Sand Dunes at almost sea level, to rock crawling at 8,500 ft. I am also not interested in using race gas, only pump gas for me.

There are a few turbo kits out there, but I was concerned that while they might do well in a sand dune environment, they wouldn’t fair so well in a rock crawling situation where it is all about low end grunt.

After researching my options, I decided that a Stage 3 Big Bore Engine Kit from Holz Racing Products would fit my needs the best. Holz worked with Kroyer Racing Engines to come up with this masterpiece of a kit.  Although the kit has proved its power on the track, what sealed the deal for me was the durability that you get with a pump gas, natural aspirated motor.

Holz/Kroyer Stage 3 Dyno Chart
Holz/Kroyer Stage 3 Dyno Chart

This engine kit is probably the most complete engine kit I have seen for a UTV.  Starting with the ported head that has been expertly machined on a 5 axis CNC and outfitted with oversize valves and springs – the head sits atop a Big-Bore Cylinder with matching 11:1 compression pistons. The cylinder also has been CNC bored and coated with Nickel Silicon Carbide cylinder coating (Nikasil). Complementing the ported head and larger valves is a billet CNC machined Hi-Lift/Duration Cam with stout chromoly push rods and hydraulic lifters. Fuel is fed through a 46mm bored throttle body and a billet aluminum intake manifold. Also included is a new adjustable PRV (oil pressure relief valve), which will help ensure that your new motor parts are bathed regularly in Joe Gibbs Racing oil. Topping it all off is a gasket kit, clutch kit, ECU ignition upgrade, break-in oil and filter, and new iridium spark plugs.

Ported Head Looks Ready for Business

Before I dropped all the parts off, I checked out some of the parts and was very impressed with the porting and the size of the valves.


Rock Crawling:

I took the RZR up toStrawberry Pass Trail for a ride.  This trail starts at about 6,000 ft. in elevation and climbs to over 8,500 ft. And along the trail are a few rock sections where you need to slowly climb up and over some large rocks. It was a perfect test and I was thrilled with the outcome. 

This was the first trip on the new engine, so I was a little nervous.  But everything ran perfectly.  I definitely noticed a nice power increase.  The tuning was spot on and the clutch settings worked perfectly.

Sand Dunes:

I was finally able to get out to Sand Mountain in Nevada for a test of the RZR. I decided to keep the Maxxis Bighorn tires on it so it would be more of a test to get to the top of Sand Mountain.  I was able to get it to the top of the mountain before with the Bighorns, but it was much more of a struggle.  Now I don’t even have to think about it. Nice to have the extra power and I can’t wait to put the paddles on for the next trip!


Holz/Kroyer equipped Polaris RZRs Dominate VORRA UTV Season Opener

Polaris RZR - Jon CrowleyPolaris RZR

Other Photos:




Contact Info:

Holz Racing Products

Holz Racing Products

Phone: 360-398-7006

Website: www.holzracingproducts.com

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