Two Brothers Exhaust and JuiceBox Review

We give our '09 Suzuki Z400 a power boost

Story by Jeff M. Vanasdal, Photography by Jeff M. Vanasdal & Two Brothers Racing, Jan. 28, 2009

Although most manufactures are building larger displacement ATVs, the Suzuki QuadSport Z400 remains one of the most fun and versatile machines available today.

For 2009 the Z400 was handed down several major upgrades, including fuel injection from the Suzuki QuadRacer LT-R450. Despite the numerous updates and fuel injection system, we felt like the Z400 needed a little extra grunt to keep it out from under the roosts thrown up by the 450cc machines. We chose to give our 09’ Z400 a little more attitude by adding an exhaust and fuel controller from Two Brothers Racing as well as an air filter from No-Toil.

Installation of the Two Brothers exhaust initially was a little different than your average exhaust installation. The Two Brothers Exhaust comes in three parts; the muffler, ‘X light’ ring, and slip-on tube. Two Brothers chose to manufacture the exhaust in three parts to avoid using any welds, making the exhaust stronger and installation easier.

Two Brothers recommends pairing the slip-on exhaust with its JuiceBox fuel controller optimum results.

With the exhaust coming in three pieces you can maneuver the slip-on tube so it’s easier to line it up with the head, thus making it easier to actually slip on. Sometimes with exhausts from other manufacturers you have to fight with the slip-on and header to be able to line up the bolts correctly.

More power = more air!

Two Brothers recommends purchasing a fuel controller with its slip-on system. The JuiceBox, as Two Brothers calls it, lets you control the settings of how much air/fuel mixture is provided to the engine. This JuiceBox is sort of like jetting your ATV but it’s much more efficient and offers a user-friendly design so you can change the setting on the fly without any help.

With the JuiceBox fuel controller integrated into the heart of the Z400 there is no longer the hassle of spending hours of your time trying to find what jet and air/fuel mixture setting works best. The fuel injection system along with the Two Brothers JuiceBox will automatically adjust the air/fuel mixture no matter what the altitude or weather condition. The JuiceBox was amazingly simple to install. All that was required was to remove the gas tank shroud, loosen the gas tank, and plug the JuiceBox directly into the stock wiring harness. Simple as that!

As an added bonus, the colors of the Two Brothers logo match the colors of the Z400 almost perfectly.

Two Bothers claims that its M-7 V.A.L.E. slip-on exhaust system along with the JuiceBox fuel controller will deliver +3 horsepower and +3 ft/lbs of torque over stock. Not only does Two Brothers claim this system will deliver more power to your machine, but it is also more than two pounds lighter than the stock system.

The power that the Z400 delivers with the Two Brothers system is almost immediate. Throttle response is much snappier and we found the front end wanted to lift a lot easier. We could feel a noticeable power gain in almost every gear. With the additional horsepower we wanted to insure we were getting plenty of clean air flowing into our modified machine so we swapped out the stock air filter and installed a new air filter from No-Toil.

Lifting the front end of the Z400 was a lot easier once we attached the slip-on exhaust and fuel controller.

The sound that the V.A.L.E. M-7 slip-on produces is similar to what a 450cc machine would put out. Compared to stock, it is much deeper and just a bit louder. The V.A.L.E. M-7 canister is also installed with a U.S. Forestry Service approved spark arrestor screen to keep the Rangers off your back.

If you are looking to give your 09’ Z400 an extra kick, or even want to catch your buddies on their 450cc machines we would highly recommend taking a closer look at Two Brothers V.A.LE. M-7 slip-on exhaust system and the Two Brothers JuiceBox as well.

Related Reading
2009 Suzuki QuadSport Z400 Review
Dubach Racing Competition Exhaust Review