The NTC 365 and 400 horsepower engines are identical except for the fuel pump calibration. If you want a 365 BCIV engine and would like to increase your horsepower to 400, or even to 425, just stop by our shop in Pittsburgh and we'll recalibrate your pump. You'll gain 1 gear on the mountains. Your fuel mileage will probably increase because you will not be spending so much time crawling up the hills.

Now let's compare the 365-400 horsepower engine to the NTC 444 h.p. To gain another 44 horsepower, all that Cummins Engine Company did was drop the compression ratio by .5 and retard the timing by .003 and increase the injector flow. In past articles we have talked about always increasing the flow of the injector to gain horsepower. The main reason for this is to decrease the pressure on the injector pushrod, which in turn increases pressure on the camshaft. Remember, that we mentioned that on a stock engine, the shock load on the pushrod is 3,000 p.s.i. If you increase your fuel pressure more than 10% you will damage your camshaft unless you increase the flow of the injectors.

When it's time to rebuild your NTC 365-400 always install the NTC 444 pistons and injectors and have your pump recalibrated to an NTC 444 code. Leave the timing and the turbocharger alone, and you will have 444 horsepower.

Most owner-operators would not be happy with only 444 h.p. If you purchase your parts from Diesel Injection we will ceramic and teflon coat the pistons, supply you with a mapwidth-enhanced high altitude turbo, increase the injector flow and install a high-volume gear pump on your fuel pump. That is your recipe for a nice running 600+ horsepower STC BCIV 88 Cummins engine.

  We highly recommend the liquid filled fuel pressure gauge and manifold pressure gauge so that you will be able to know how much horsepower you are using.

Its a shame the STC injectors had so many problems during their first several years of production. However, we feel that most of the mechanics in this country never understood the proper method for installing and tuning an engine equipped with STC injectors. Another way to extend the injector life is to clean the oil better by installing a Harvard luberfiner filter, which filters to 1 micron in size. Your standard oil filter is around 38 micron. Another great item is the Spinner II Centrifuge oil cleaning system. This will actually spin the contaminants out of your oil and with both filtration systems you can easily increase your oil drain intervals by 50%. This will save you approximately $1,800 in oil changes plus your time. The cleaner oil will greatly extend the life of the hydraulic tappet. It fills with oil to advance the timing of the injector to eliminate white smoke during idling. Dirty oil will score this tappet and ruin a $1200.12 set of injectors. Also, your engine life will be greatly increased due to the elimination of dirt in your engine oil. Please keep this in mind, if your engine had a constant supply of clean oil, the engine would never wear out. Metal never touches metal in an engine, the contaminants or dirt in the oil causes the wearing of bearings, liners, bushings, gears and thrust washers.

Used conventional trucks with BCIV 88 STC engines (NTC 365-400 & 444) sell for $3,000 to $8,000 less than the identical truck with a 425 h.p. Caterpillar engine. Take advantage of these savings. Buy the truck and install the high flow pump, injectors and mapwidth-enhanced turbocharger and you will have a great running truck that you will love to drive.

Just a short note about camshafts: The high lift cam that we use in our engines is not the CPL 676 BCIV camshaft. The BCIV 400 cam does have more exhaust valve lift, which presents a problem for our high strength ceramic and teflon coated pistons. The exhaust valves will hit the pistons during a hard pull if you use this cam. You have to use a specific piston in CPL 676. Our high lift cam has 42 thousandths more travel to the injector than all of the standard Cummins cams.

Please do not call and ask for part numbers of the products we work with . If you world prefer to build your own engine, that's fine. We will supply the parts, technical information and answer all your questions. If I can't sell you the parts I won't be in business very long and then we won't be able to help you build your high-performance engine.

Vibration Dampers: Several months ago we talked about all of the components that break because of faulty dampers. After a brief conversation with the manufacturer of the dampers we have learned about a few more problems such as slapping belts, excessive bearing wear and excessive gear wear in the front cover of the engine.

When the injector injects the fuel, the force of the explosion pushing the piston down is like smashing the aluminum piston with a hammer. That causes a torque spike, which twists the crankshaft. When the crankshaft twists back after the pressure is gone, the result is a torsional vibration. The damper absorbs this vibration and saves the crank, cam, accessory drive shaft and flywheel mounting bolts from breaking. The manufacturer of the damper recommends changing every 380,000 miles or 15,000 hours.

Let's talk about the force that drives the piston down. In past articles we have talked about timing. As horsepower goes up timing must be retarded and the compression ratio of the piston must be lowered. When the timing is retarded the piston is closer to top dead center when the fuel is injected. While the piston is at top dead center is when the hammering effect takes place. Until the crankshaft starts its downward stroke, which is a millisecond, the piston is subjected to severe abuse. This is why we ceramic coat the top of the pistons. It's much more durable than aluminum. When working the engine on a mountain or against a headwind its much easier on the piston if you keep the rpms up around 1900 to 2100. This gets the piston out of top dead center faster. We set all of our fuel pumps to pull at least 2300 rpm on our performance engines. 2300 rpm does not hurt an NTC Cummins engine. When our owner-operators are drag racing, such as at Englishtown, NJ or pulling sleds at county fairs, they will run the engine as high as 3,000 rpm. We have never had a failure using high rpms. A smaller amount of fuel gets into the injector cup to be injected into the cylinder. Horsepower drops off after 2500 rpm. Cruise your engine at 1500 to 1700 rpm. Work it at 1900 to 2100 rpm, always are in a gear where you can accelerate if you put the throttle to the floor. By the way, check your throttle linkage to be sure your getting full throttle. The Cummins brake-a-way lever on the fuel pump should brake-a-way about 1/8'' when the foot throttle is on the floor.

Air Cleaners: Just because you have a conventional with dual air cleaners doesn't mean you have enough CFM (Cubic Feet per Minute) of air. Measure the inlet and outlet of the air cleaners, if they are 5 to 5 1/2'' you may be starving your engine of oxygen. The new Ford Aero Max has a very restrictive pipe coming from the air cleaner to the turbo. Be careful if you want to build a big horse in that chassis. You may have to get very creative with the air filtration system.

Driving a 700 plus horsepower Cummins engine is a unique experience. Just moving your big toe brings response. During the month of December, we built for Wayne Reighard from Lititz, PA and Vernon Harris from Martha's Vinyard, Cape Cod, 1000 plus horsepower engines. Their trucks, a 1985 Marmon and 1983 Peterbilt came equipped with NTC 475 twin turbo engines. Wayne has a 3:36 and Vernon has a 3:42 gear ratio. Wayne, running in direct gear (12th), topped Snowshoe Mountain at 70 mph at 1800 rpm using only 200 lbs of fuel pressure while grossing 79,000 lbs. Dwain Pyeatt did the same thing last year and nobody would believe it. Wayne Reighard pulled the same mountain at 200 rpm less because he has 3:36 gears and Dwain has 3:55 gears. I'm sorry some of you have to use your four way flashers on Snowshoe Mountain. Please just make sure you stay in the right lane.

The ceramic engineer that coats our pistons with ceramic and teflon called last week to inform us that he has changed the formula and its now called Ion Bonding instead of ceramic. He claims the Ion Bonding is much stronger than the ceramic. The teflon is still on the piston skirts. This engineer also coats Paul Newman's pistons for his racecar. If you're rebuilding your engine, regardless of what it's in, you should allow us to coat your pistons with the Paul Newman formula, Ion Bonding and teflon. To keep things simple, we'll continue to call it ceramic.

We also have high performance parts available for the dodge Cummins pickups. Turbos, air to air intercoolers, exhaust systems, pyrometer and manifold pressure gauges and tachometers. If you operate your Dodge at high altitude with a stock turbo, you're in trouble. Your exhaust temperature is in excess of 1400 deg. You need our performance exhaust housing and a pyrometer.

Now, on to the block and piston preparation. When you are doing an out of Chassis rebuild and having your block resurfaced, always tell the machine shop to remove as little as possible from the deck surface and have them inform you as to how much they machined off. If you purchased your truck used, and are not sure if the block was ever resurfaced, you should check the piston to deck surface height. If too much material was machined off your block you can have the valves hitting the pistons. Always be aware of the fact that not all pistons have the same amount of depth to the valve pocket even though the compression ratio may be the same. This is especially true in BCIV 400 and newer engines.

To measure the piston to block deck height, bring the piston to top dead center and measure the distance from the top of the outer rim of the piston to the block deck surface, bridging over the liner. Do not measure into the valve pocket. The diesel shop supplying your parts will be able to give you the correct measurement for your engine. If your block is too short, we have head gaskets that are .013" thicker so you won't have to scrap the block.

Another use of these special gaskets is for lowering the compression ratio. If you have an NTC 350 and are going to install head gaskets, use the .013" gaskets. Install NTC 400 injectors and you have an NTC 400 with 350 timing. This engine will be very responsive so be gentle on the throttle. The next time your into the camshaft, time the engine to 72 or 73 and the pistons will live longer. An NTC 350 and 400 use the same cam key so you won't have to remove the cam to change the key. just decrease the amount of gaskets on the cam followers. Any questions just give us a call and we'll make sure you have the right parts to have horsepower.

When the government of the United States made it mandatory for all of the on highway trucks to use low sulfur fuel, we suffered with low power, stuck injectors and leaking fuel pumps. We had numerous phone calls from owner operators asking what can they add to their fuel to help gain back the power and fuel mileage they lost. In my brother's 444XT and my Dodge Cummins pick up we tried many products to see if they would work. Unfortunately, no change in power or fuel economy, I thought we were going to have to live with garbage fuel.