DIESEL ENGINE BLOCK K19 DIESEL ENGINE PARTS CYLINDER BLOCK 5260561 3088303 ENGINE BLOCK PARTS

Cummins blocks can withstand more than a 30 percent increase in power and torque. Duramax and Powerstroke blocks, on the other hand, can only handle about 13 percent more (with stock internals).
Most of RDP’s builds are under 1,250 hp, so the stock block is sufficient enough to handle the power load. However, he says that on the Duramax, even with a billet crank, it can easily snap with that much power due to the V8 layout. The Cummins blocks are more robust because they are naturally more balanced as an inline six-cylinder so that you can get more power out of the stock bottom end.

Engine Builder Contributor Doug Anderson notes that with diesel cylinder blocks, unlike gasoline blocks that may only deal with 25-35 pounds of pressure, diesel can be as much as 250 psi! “One of the problems is it tries to lift the head up off the block, so they use a girdle in the bottom of the block and a girdle across the top of the head to try to keep it all in one piece.”

A significant percentage of the money spent on a diesel performance build, according to Anderson, is on the cranks just to withstand the high pressures. “The engine has to be able to withstand the boost and keep the bottom end from blowing up… How many RPMs do you think a pulling engine turns off the starting line? They can turn 6,000 rpm! For a diesel, that’s like hitting 10,000 in a gas motor. The crank weighs 200 pounds, and it’s swing around at six grand with 250-lbs. of boost pressure. There ought to be a law against it! I’ve watched a couple of them blow up, and it’s quite a sight.”

According to Strube, “At the levels I am building for, the most important aspect is to ensure the rotating assembly is balanced. This is key to making the assembly stay intact. When bottom end strengthening is necessary, a girdle usually addresses those concerns adequately. Obviously, studding the mains and cylinder head(s) are a must as well as upgrading the crankshaft in some applications.”

Using a stock block for any performance build has its share of pitfalls, and depending on what you’re building, an aftermarket block or billet block may be the safer option