800 HP Big Cam and DD15 One Box Sensors

2021, Big Cam Cummins, DD15 -

800 HP Big Cam and DD15 One Box Sensors



High performance trucks are a keepsake! Chuck Carlson of Western PA owns this beautiful 4300 IHC originally powered with a Big Cam III 400 horsepower Cummins engine. Once it was time for an in-chassis rebuild he brought it to our shop for an ultra high horsepower rebuild back in the late 1980’s. After disassembling the deck surface was cleaned, inspected for cracks, upper counter bores miked for liner protrusion and concentricity, and upper counter bores machines for .020 liner shims. We then installed new cam bearings, a high lift camshaft, and timed to a retarded setting. Always retard timing when power is increased. New main bearings were installed along with ceramic and Teflon coated high strength Cummins pistons. These pistons were designed for our performance engines by my good friend Mark Chappell, the performance parts engineer for Cummins in Columbus, IN.  Performance parts included: Premium Golds heads, ultra high flow injectors, fuel pump built by Pat Sharp (37 years with Pittsburgh Power), our Holset high altitude polished turbocharger, dual fuel line kit, dual power valve to make this a 2 stage engine.  Why 2 stages? With 800 plus horsepower under your right foot that is super responsive, it’s nice to be able to have a lower horsepower setting black ice, snow, sand, gravel or soft dirt.  And as always we installed a new Torsional Damper to keep it running smooth for another half a million miles. Chuck currently drives a much newer electronic engine powered truck, however this 35 year old IHC has a special place in his heart!


On maintaining emissions systems, it’s vitally important you use preventative measures to keep your emissions systems working properly so they do not fail and cost you more in the long run. Not only are the particulate filters expensive to replace, but the costly sensors can also fail if not maintained. For both the DOC and SCR you have inlet and outlet temperatures sensors. The DOC has inlet and outlet pressure sensors and the SCR has inlet and outlet NOx sensors. That’s a lot of sensors. If not maintained carbon buildup and oxidation can permanently damage them. In addition, the sensor bungs can oxidise and seize so it’s difficult to remove a sensor without damaging the bung or sensor. If you take a look at the photos included here, they are from a DD15 with 600,000 miles and the emissions system was never serviced and never cleaned. We tried to clean the DPF but there was a sizable chunk of the filter missing. You can also see the poor conditions of the sensors, specifically the rusted threads. As you know, in addition to servicing your emissions system every 250,000 miles, we recommend running the Max Mileage Fuel Borne Catalyst to keep everything clean and working correctly.