​The Marinized Series 60 Part 2: Unlike The Trucking Industry - All Our Engines Are High Performance

As far as peak torque and horsepower output the marinized Series 60 is king of the production Series 60 engines. But what about efficiency? For years I’ve been told marine camshaft and injector combinations were powerful but not efficient. Doing a live dyno test on a Marine engine is hard to do. They make so much more power and rpm that fuel efficiency comparisons are difficult and often inconclusive. I’m an advocate for using real world data anytime I can eliminate outside variables but for these tests I am going to use the DCS test bench and Detroit’s fuel consumption calculations that are specific to the 14 liter marine Series 60 and the 2002 14 liter highway Series 60. Years ago I compared Detroit’s fueling calculations to brake specific fuel consumption data I collected from live tests and found it to be very accurate as long as the engine and the DDEC program were not modified.

To compare these two engines based purely on efficiency we need to test them at rpm and torque thresholds that they can both reach. So while I run this test I will be throttling back the marine S60 DDEC so the highway DDEC can keep up.

My goal here is to determine if these calculations support the claim that the S60 marine camshaft and injectors are responsible for loss of fuel economy.

Most would agree idle is when an engine is running but total flywheel horsepower equals zero. Idle load fuel consumption on a truck is tricky to calculate because total engine load is light and a relatively high percentage of total load comes from belt driven accessories like the engine fan, alternator, and AC compressor. In a marine application those parasitic losses are more predictable and generally less than that of a truck. No engine fan, or air compressor to worry about and generally the cooling systems are more efficient. The DDEC IVs that I am using for this test take these parasitic losses into account so testing these two at idle isn’t going to be fair. Both of these programs are bone stock.

The first test is at light load between 1200 rpm and 1800 rpm. Torque output is set to 500 ft-lbs

The second test is at 1000 ft. lbs between 1200 rpm and 1800 rpm.

The third test is at 1650 ft-lbs between 1200 rpm and 1800 rpm. These are 14 liter engines so they can produce this all the way up to 1800 rpm.

The final test is at 2000 rpm. The highway 14 liter program can only go to 1450ftlbs at 2000 rpm.

I admit, this didn’t turn out like I expected. Despite having larger fuel injectors and a more aggressive camshaft fuel consumption is slightly lower than the highway 14 liter Series 60. Could it be the marine engine’s aggressive timing? Maybe. I’m going to look into this further and I’m NOT sold…yet.

Written by Fernando DeMoura
Diesel Control Service LLC.
Website: www.dieselcontrolservice.com
Phone 412-327-9400