Genuine Dongfeng Cummins 6L Diesel Engine Cylinder Block 5260558

GENUINE DONGFENG CUMMINS 6L DIESEL ENGINE PART CYLINDER BLOCK 5260558 DIESEL ENGINE BLOCK  “Every platform has inherent weaknesses according to the environment it operates in,” Strube explains. “Stock castings have been heat-cycled thousands of times. Most often, this strengthens the iron composition. However, overheating, bearing failures, decomposition of the iron due to electrolysis, poor coolant/oil contamination will all definitely, result in a shortened lifespan of that foundation.”

The risk of block damage increases the higher you go in boost pressure and horsepower, says Strube. “On a higher output level, the main journal landings can give it up under extreme torsional distortion and result in compromised integrity. This can lead to complete failure where the block cracks/separates, and subsequently, the rotating assembly fails to remain intact.”

Aftermarket billet blocks have tremendous advantages in these prone areas, according to Strube. He says they have significantly increased material strength, reinforced cylinder structures and the increased oiling capacity enable these platforms to withstand exponentially higher output environments. But they are also exponentially higher-priced, and for many diesel performance enthusiasts, a 3,000 hp engine is not in the budget. To this end, some cast iron aftermarket blocks are beefed up in critical areas to handle high power output.

Under normal circumstances, clearances are not an issue on stock blocks if you’re stroking them and adding billet cranks and main caps. Strube says the manufacturers have gone to great extents to provide well-engineered components in most applications. “The issues are encountered when trying to mix components from various companies. Obviously, company A is not going to assume for the design variations of company B and C if one should exist. These complexities are the job of the builder to overcome.”

The biggest challenges builders have with setting up the blocks for a big horsepower build are more from a financial standpoint than anything. Getting customers to understand that power has a price, and there’s only so far you can push the envelope on stock parts, can be a challenge.

“The average application we build for is rarely above 1200 hp,” Strube remarks. “This doesn’t require much in the way of adding to the foundation to support more power. The biggest challenge is developing a clear strategy that provides the customer with a dependable power assembly, capable of withstanding the desired output and remains within the declared financial means.

“Far too often, the customer likes to push the limits of the foundation with less funding than required. There are naturally thresholds for upgrades such as a stock crankshaft or valvetrain assembly. If the limit on a stock crank is, say 800 hp (arbitrary value), some customers like to knowingly push that assembly to 850 hp or more simply because the next level upgrade would be $8k or so and they don’t want to invest that amount. Power desires tend to grow rapidly. Unfortunately, these desires outpace the wallet in some cases!”

Hamilton Cams in Texas makes beefed up diesel blocks for Cummins applications. Their 6.7L block is made for off-road only competition purposes and can conservatively handle up to 2,000 hp. For customers who want big power but don’t want to spend $15k on a billet block, this may be a good solution. The block features a 4.210˝ bore and is machined for 14mm head and main bolt hardware. The seven cam bushings come already installed for 54mm cams. The company says you can push the envelope on valve motion with a 55mm cam bushing upgrade by pressing out the 54mm bushings and pressing in thinner 55mm bushings.

According to their website, the block can handle 3,000 hp in some applications where it is not being loaded hard at low rpm. The higher the rpm that horsepower is made, the lower the peak cylinder pressure. Hamilton says they are currently working on redesigning the block with higher tensile 300mpa cast iron and improved cam oiling and main supports.

Wagler Competition Products in Odon, IN, has become synonymous with diesel performance and offers many aftermarket products to beef up the stock block. The company’s Streetfighter Duramax short block, for example, includes a prepped block (LB7 – LMM), front cover, rear cover, upper and lower oil pan, Callies forged Compstar 6.6 Duramax crankshaft, ARP 2000 main studs, Wagler As-forged Duramax Street rods, Wagler de-lipped Mahle pistons, Wagler Stage 1 AF camshaft, new GM crank gear, and a Wagler pinned oil pump. The short block is also externally balanced for the OE Duramax harmonic balancer and flexplate, but they can also balance for other dampeners.