"Every motor we build is dyno'd and goes through a strict break-in process. We first fire up the motor and hold it between 2,000 and 2,500 rpm without any load placed on it at all. The timing is set, and once the engine reaches operating temperature, we set the idle mixture and place roughly 25 lb-ft of resistance on the motor. We gradually increase the load, which helps seat the rings, then tune the carb for idle quality, midrange power with and without load, and WOT. Next, the accelerator cam and squirters are adjusted on the carb. After one light-power run is made to 5,000 rpm, three full-power runs are made up to 6,000 rpm, at which time the engine usually picks up about 10 hp. Finally, a post-dyno inspection is performed to verify that there are no oil or coolant leaks. Customers receive the dyno printouts of their actual motor showing horsepower, torque, oil pressure, and water temperature from 2,500 to 6,000 rpm.
Most hot rodders use well-worn blocks as the foundation for their engine builds and never think twice about it. However, there are some drawbacks to using a block that has seen a fair amount of miles. "When a cylinder wears, it wears off to one side instead of wearing perfectly centered," Ben explains. "When you blueprint the block, are you going to machine it where it's at or machine it to blueprint specs? With most blocks, there just isn't enough meat to machine a cylinder to where it's supposed to be. Another benefit of using a new block is that there is no rust in the water jackets that could compromise the cooling system, and the newer casting technology is better as well."
In the right hands, battle-tested, old-school equipment is plenty capable of producing beautifully machined blocks, but there are significant advantages offered by modern computer-controlled equipment. The main benefit is consistency. "An automated machine doesn't care if it's in good or bad mood, so it will do what it's supposed to all the time," says Ben. "Automated boring fixtures ensure that the bores are properly located. Also, by combining automation with diamond cutters, honing machines can produce finishes that were unheard of just a few years ago, which results in faster break-in, reduced friction, superior ring seal, and improved durability."
The area under the curve, or average horsepower, is far more important in a street motor than peak horsepower. Consequently, a motor with lower peak horsepower can outrun a more powerful adversary at the track if its power curve is better optimized for its operating range and a vehicle's gearing. "The issue is performance throughout the entire power curve," says Ben. "If you take the dyno numbers of two engines, add up the power numbers they produce at each 500-rpm increment, then divide that sum by the number of increments, you get the average horsepower produced over the entire rpm range. A broad powerband with lots of low- and midrange torque may sacrifice some power up top, but it can still post a higher average horsepower figure than a peakier combination. That translates into better drivability and better track performance."It's nice to have power at peak rpm, but when you go to accelerate in most instances, you're at a lower rpm. Nothing's nicer than gassing it at 2,500 and having the car take off.