35+ & 35++ Upgrades

40 and 44 hp Vertical & Horizontal Shaft mud motor engines are now available.  All engines are modified, tuned, and dyno tested to verify performance numbers. Dyno sheets will be provided with each engine sold. 40 and 44 hp modifications are offered for new or customer supplied engines.

Our kits are real world tested, and horsepower gains are verified. Our kits do not sacrifice bottom end torque, mid-range acceleration, or top end performance. Don’t spend money on a staged kit, or modifications that do not verify torque and horsepower gains.

* Connecting with a reputable dyno operator is clearly the first objective when planning a dyno test. 
Doug has over 30 years of experience with engine and dyno work.   

Stock & Modified 35HP engines are in stock and ready to install on your mud motor / shallow water frames.






Manufactured in Louisiana

 2015 Boss Drives Product Sheet - Click Here

Standard and Grass Camo paint available. Remote steering motors with industry leading control systems are now available upon request. 

* Vanguard Large Block Engine * Cone Clutch F-N-R
* High RPM CDI Coils * Heavy Duty Gearing
* Cast Aluminum * Stainless Exhaust
* Big Blade Propeller * Moto Cross Comfort Grip
* Patented Bearing and Seal System * Transmission Oil Site Glass
* Mercury Electric/Hydraulic Trim * Adjustable Floating Handle
* Universal Outboard Mount * Tach/Hour Meter
* Marine Wiring * Locking Hand Shifter
* BPS Sqeeze Throttle Lever  

Engine ModelHeadCarburetorRodCamPistonMuffler
H3500 Vanguard Vanguard Vanguard Vanguard Vanguard Vanguard SS
H3700 (EFI) Vanguard Vanguard EFI Vanguard Vanguard Vanguard Vanguard SS
H4400 Iron Mt. Mikuni 42mm Vanguard Vanguard Vanguard BPS Muffler

Boss Drive Mud Motors