What should racers and engine builders discuss when it’s time to choose an engine block?

So many factors come into play when choosing a race engine block. Iron or aluminum? Cast or billet? OE-based or aftermarket? Solid or water-cooled? Deck height? Cam location? Power adder? And the all-important one: How much horsepower do you want to make?

"There has to be a good conversation between the racer/customer and his engine builder, so they get on the same page," said Ben Mens of Energy Manufacturing, Fremont, Ohio. "That way everybody knows going forward what the engine's going to be. The customer needs to understand what he needs to reach the performance potential to shoot for his goals, and the engine supplier should know the requirements for that combination."

We spoke with engine block and sleeve manufacturers to get ideas on how to get to that "good conversation" Mens spoke about. What questions need to be asked by—and of—the racer? And what are some of the trends in race engine block design and manufacturing to help steer that conversation?

Any Power You Want

Energy Manufacturing's engine blocks "are all solid billet, not water cooled," Mens said, "so our customers are all drag race customers." Block platform choices include LS, big block Chevy, and small block Ford.

Energy offers a range of bore sizes, cam bore options, and lifter configurations for each platform. "And we raise cams in relation to the crank bore and give room for increased stroke and the big power adder connecting rods so that everything is going to clear and be happy," Mens said. "We also build very stout lower ends, so it'll hold about any power you want."

Bill Mitchell said his company’s aluminum blocks, like the Gen II Hemi shown here, “were always pretty stout.” But to keep up with the stress generated by higher power targets, he has “increased the thickness of the main webbing and added more material and more structure.”

Elaborating on that "good conversation" between racer and engine builder, Mens believes there needs to be "a commitment on both ends" of the discussion. "The racer should commit to wanting the best for his program and ensuring he has the best opportunity to realize success. Then the builder should commit to being forthright and honest, telling the customer, 'I need you to have these top-shelf billet components and everything else that goes with them to create what you're expecting from me as the builder to meet your goals.'"

Mens recognized that not every racer has unlimited funds. But rather than skimping on the engine block, he suggested the use of "mid-level performance" components in the engine buildup, like a forged crankshaft instead of billet, or a set of cast heads. That's a "much better choice than putting great parts in a weak block and hoping it keeps everything where it needs to be."

Racers should also have "a solid foundation for anything they do in the future. The power adder portion and the EFI systems seem to be on a high-end improvement curve all the time. If a racer had, say, a smaller supercharger or turbocharger or a single and wanted to upgrade to twins or something like that in the future, you definitely have room to grow" with a billet block.

Racers should "plot out and plan ahead," Mens said. "Maybe you don't have the money for a billet block today, but it's still going to take you 10 to 12 weeks to get one from us if we start from scratch. You have time to gather things."

Correct Block Every Time

Scott Patton of M&M Competition Engines in Franklin, Indiana, provided a succinct list of questions racers and engine builders should discuss: Type of racing? Any weight concerns? Size of engine (and any plans of changing this down the road)? Any power adders (and any plans of changing this down the road)? What is the horsepower goal of the combination? Any rpm limitations?

"With an in-depth conversation about these questions, the racer should end up with the correct block every time," Patton said.

M&M caters to the "high-end drag racing market," he said, with cast-iron blocks "that can withstand the abuse of high-revving naturally aspirated applications along with extreme power-added applications." Because M&M makes its own tooling, has its own foundry, and has a machining center, "we can begin with a clean sheet of paper and create a block design that incorporates not only the necessities that the market needs, but also technology options that have never been offered to racers."

M&M's Evolution block, for example, incorporates...

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Sources

Bill Mitchell Hardcore Racing Products
billmitchellproducts.com

Dart Machinery
dartheads.com

Darton Sleeves
dartonsleeves.com

Energy Manufacturing
energymanufacturing.com

LASleeve
lasleeve.com

M&M Competition Engines
mmcompetitionengines.com

World Products
pbm-erson.com