This is the 50th article that we have written pertaining to Cummins diesel engines and how to produce as much as 100% more power using genuine Cummins engine parts. All of this power would not have been possible if it weren’t for the help and dedication of one particular Cummins engineer, Mark Chapple of Columbus, Indiana. Mark has been my guiding light and closest friend in the relentless pursuit of producing horsepower from the Cummins engine.

 

Mr. Chapple started with Cummins right out of high school at the age of eighteen. His first job was on the assembly line putting engines together. While working daylight he enrolled in night school at a college in Indianapolis studying mechanical engineering. Prior to graduating from college the management at Cummins saw the potential of this young man and promoted him to the engineering department.

 

I had the privilege of meeting Mr. Chapple on the phone around 1984 after placing a phone call to Columbus, Indiana asking for the engineer responsible for developing the small cam Magnum 400 Recon engine, CPL 695. I was transferred eight times before getting Mark on the phone. My question was how can this engine start, let alone run with a timing of .056 and a compression ratio of 14.0 to 1. Mr. Chapple spent the next two hours explaining to me the effects of compression ratio, timing, injector flow, injector cup size, fuel pressure and volume and what happens if you don’t follow certain guidelines when increasing horsepower in a diesel engine.

When that phone call ended I knew that I had a new friend and my life and the life of every owner-operator in this country that drove Cummins engines was about to change. One of the projects that Mark Chapple and I worked together on was to develop 700 horsepower from a BCIII engine using STC injectors, twin aftercoolers and twin turbos. This engine produced 700 horsepower on the dyno at Cummins in Monroeville, PA. and was installed in Jerry Hairhogger’s Kenworth from Wampum, PA.

 

In January 1996 while I was visiting with Mark in his office he opened a letter which changed his life. At the young age of 51 he had enough seniority to retire. This man truly loved his work at Cummins Engine Company and did not want to retire. However, the retirement package was too good to refuse. Mark Chapple, Cummins engineer extrordinaire, is now at home in his own shop developing high performance engine parts for Dodge Cummins trucks. Mark’s 1995 Dodge produces over 300 horsepower and runs 0 to 60 mph. in eight seconds.

 

For those of you who have been following our articles for the past 50 months now you know where a lot of the technical information that has been made available to you has come from. As Paul Harvey would say, now you know the rest of the story.

 

With great pleasure I dedicate this 50th article to you Mr. Mark Chapple for all of your help, understanding, knowledge and friendship during the past twelve years. Thank you.