JJB Marine Specialists are proud to be the official appointed UK dealers for

Swaymar Marine Engineering Ltd.

Swaymar Marine is a specialist inboard engine tuning company for petrol sports performance boats. JJB Marine Specialists supply and install these high performance power units into your boat.

These Special Series engines are specifically designed around the Small Block and Big Block V8 Chevrolet engines and provide significant performance, reliability and efficiency improvements over their standard manufacturers counterpart.


Crucially we have designed our engines specifically for marine use, delivering vastly increased torque several hundred RPM lower down the rev range.


Once combined with the correct pitch propeller, this results in a faster boat at lower RPM, consequently it will therefore consume less fuel at any given cruise speed.


Silver Wraith Series: 

V8 Small Block Chevy 305-427cid

  • 5.0L 280 hp  

  • 5.7L 335+ hp

  • 6.2L 380+ hp

  • 6.5L 400+ hp

  • ​7.4L 365 hp  


Silver Phantom Series: 

V8 Big Block Chevy 454-540cid

  • 8.1L 430+ hp

  • 8.3L 450+ hp

  • 8.8L 525+ hp