Best Dual Engines To Buy For A 2005-2008 340 Sundancer and Why?
- Thread starter Tabasco
- Start date
Jimmy Buoy
Well-Known Member
- Dec 3, 2008
- 2,464
- Boat Info
- 2003 Cobalt 293
- Engines
- Twin Volvo-Penta 5.0 270hp & DuoProps
I had an Amberjack 340 with twin 8.1's (496 cubic inch) which were great torque monsters - perfect for a boat that size. Older 454's might have higher hp numbers but will not provide the same torque across the entire rpm band. The 8.1's are quite detuned with a more restrictive intake/exhaust ports than needed and are capable of much higher power figures using different heads/exhaust but it might have been Merc/GM choosing engine longevity over raw HP figures. Iron block and heads along with distributor-less ignition and the PCM555 computer its quite the package. All 8.1's offered by Merc were identical.
On the negative side, GM no longer makes this block (since 2008) so engine replacements are becoming a rarity. There are outfits that sell "factory manufactured" rebuilts though. Things that will kill this engine are the exhaust manifolds in salt water, paint chips in the fuel system, and raw water pump failures - but regular maintenance if completed will negate these issues.
On the negative side, GM no longer makes this block (since 2008) so engine replacements are becoming a rarity. There are outfits that sell "factory manufactured" rebuilts though. Things that will kill this engine are the exhaust manifolds in salt water, paint chips in the fuel system, and raw water pump failures - but regular maintenance if completed will negate these issues.
Windjammer
Well-Known Member
8.1's are the engines you want.
