High Performance Diesel Engines

Bruce Mallinson
December 2017

Broken pistons and cracked heads on the newer electronic diesel engines, WOW! Too many ECM tuners do not understand the internal workings of the turbocharged diesel engines. We are seeing many engines with the timing too far advanced. Timing NEVER gets advanced on any engine turbocharged, supercharged or equipped with a blower. It doesn’t matter what the fuel is, gasoline, alcohol, nitro methane, or diesel fuel, timing NEVER gets advanced once air is forced into the combustion chamber. If you allow a truck stop tuner, or anyone that says they can increase your power, improve fuel mileage by tuning your ECM and they do not fully understand the effects of advanced timing, your engine is at risk of breaking pistons and cracking heads. If you go back and read my articles pertaining to Big Cam Cummins Engines that used aluminum pistons, you will read about how we retarded the timing as horsepower increases. That was to decrease internal pressure on the piston and eliminate rattle in the engine when accelerating.

Let’s talk about the ISX Cummins engines. The 1998 through 2002 non- EGR equipped engine were CM570. The CM stood for control module, the 570 denotes the engine family, and this ECM has 6400 parameters which is more than the space shuttle had. The 2003 through 2007 were the CM870 EGR equipped engine, then in 2008 the Cummins ISX-EGR engine was equipped with the DPF (diesel particulate filter), and that engine was called the CM871, which ran through 2011. 2012 brought the common rail fuel system and DEF (Diesel Exhaust Fluid) was added to the DPF and EGR, and that engine was the CM2250, which ran through 2013. 2014 the CM2350 was introduced and it has just over 17,000 parameters that can be changed, and this ECM is still being used today. The X-15 ISX Engine CM2350X15 means the 7th injector was eliminated which was used to regen the DPF. The regen on this engine is accomplished by injectors #3 and 4 injecting more fuel during valve overlap to make the heat to perform the regen of the DPF. The CM2350 has a total of 45 variable timing tables, 15 timing tables for the pre-injection, 15 for the main fuel injection, and 15 for the post injection. Now take 15 times 15 times 15 or 15 to the third power and you have 3375 different timing tables the un-informed mechanic or ECM tuner could screw up. Just be careful whom you choose to have make changes to your ECM. An Engineering Marvel is the best way to describe CM2350 and the X-15 Cummins engine. It’s so smooth that you will think you have a General Electric motor under the hood.

If you think this is confusing, the Cummins ISX engines, Detroit, Mack, Volvo and Paccar engines are making similar changes. They are all very complicated complex pieces of engineering marvels. Think about this the next time you allow someone to plug into your ECM that is not a qualified mechanic or engineer, does not have a dyno to test your truck, and does not understand the internal workings of these complex engines. Be careful, you may be putting pistons or replacing the head within the next year or two. The steel top pistons in today’s engines are very strong, however, advanced timing can fatigue the metal and bore a hole through it and the head will crack. We have also seen pre-mature rod bearing failure because the internal pressures overcome the film strength of the oil. Advanced timing raises internal pressures well beyond the manufacturers’ recommendation. I had the privilege of learning this from Mark Chapple, the performance parts engineer at the Cummins Engine plant in Columbus, IN back in 1983. Mark would invite me to join him at the engine facility many times throughout the years to work on various projects. I was all ears listening to various engineers talking about the engines while in meetings, luncheons, and dinners. Mark Chapple and Pittsburgh Power continue to work together today; in fact he will be working in our engineering facility on the dynos on November 9th and 10th.

Are you committing Diesel Engine Suicide? If your truck is NOT equipped with a working pyrometer (exhaust gas temperature gauge) and turbo boost gauge (manifold pressure) you should NOT be driving it. I don’t care if you have been driving for 35 years, you cannot tell how hot the exhaust gas temperature is or if the engine has a turbo boost leak. You may hear a very large boost leak if the radio is turned down and there is not a lot of traffic around you, but most of the time you will not hear it. Most trucks today do not have a spot mirror on the top of the mirror braces, so you can’t see the stack to see what type of smoke is coming out of the stack. You will feel the power loss, maybe change the fuel filter and the power is still low, check engine light may come on, but it might not. The pyrometer and turbo boost gauge will inform you if you have the knowledge to what they are telling you. If you don’t understand them, I will teach you while you are driving your truck if you are a client of ours. You should always know about where these two important gauges are reading before you look at them. If you don’t, you are not driving your truck properly. By knowing what they should be reading you will be able to tell if you have a loss of turbo boost or a loss of fuel flow. If the exhaust temperature is higher than normal and the boost is lower than normal, the air intake system, air filter or turbocharger have a problem or leak. If the boost is low and the exhaust gas temperature is low, the engine is suffering from a fuel delivery problem or ECM calibration problem. When we get the phone call and you tell us you have poor fuel mileage and low power and want to know what is wrong, and we ask you about the readings on the pyrometer and boost gauge, and you tell us you do not have them, we cannot help you over the phone. Then we tell you to make an appointment and bring it to our shop. Most of the time the answer we get is I never get east. We can’t help you if you can’t tell us the answers to our questions. The boost gauge kit is $70.00, and the pyrometer kit is $178.00. You can install them in your driveway or a truck stop parking lot if you have some tools.

Now for something fun to do -The Owner Operator Snowmobile
Conference for January 25 through the 28th will be held at the Horseshoe Mountain Lodge in Mt. Pleasant, UT. The phone number is 435-462-9330. There are rooms reserved under “Pittsburgh Power Snowmobile Group”. The price for a room with 1 king bed is $75.00 per night and with 2 queen beds is $80.00 per night. We will meet there on Thursday the 25th and ride the Skyline Drive on Friday, Saturday and Sunday. Sherman Zeeman, retired heavy hauler owner operator from Payson, Utah, will be the principal speaker. The title of his speech will be “Trucking the old school way with gasoline engines pulling Soldiers Summit at 3 mph.” Sherman is the owner of the very first double bunk 1975 W900 Kenworth ever built. George Gallamore from the CMC will speak on Saturday night about negotiations and dealing with people.

Rental snowmobiles are available at Big Pine Sports in Fairview, UT and their phone number is 435-427-3338. They also rent trailers, however, we have to figure out how you will tow the trailer if you fly into Salt Lake.

We have 2 owner-operator snowmobile conferences per year. The next one will be at the end of February or the first weekend of March. If you have never joined us, you are missing the opportunity of a lifetime to share time with other owner-operators while playing in the warm snow and blue skies and tearing up mountains with snowmobiles with 165 horsepower that will accelerate to 60 mph in under 4 seconds.

Written by Bruce Mallinson,

Pittsburgh Power Inc.,

3600 S. Noah Dr., Saxonburg, PA 16056

Phone 724-360-4080

Website: www.Pittsburghpower.com