My admiration for the Ford 300 engine is genuine. It’s a versatile workhorse that can handle heavy loads or deliver impressive performance on the drag strip with the right enhancements. Keith Lopez from Foxrod Racing has developed an extraordinary example that surpasses any I’ve come across. Despite already generating approximately 1,000 horsepower at the crankshaft, Lopez isn’t finished with his project just yet.
This custom-built inline-six engine resides under the hood of Lopez’s Ford Fairmont wagon. It replaced the vehicle’s previous twin-turbo small-block Ford V8, which was removed and sold to finance his racing endeavors. Lopez also drives a Bullnose F-150 equipped with the same engine, complete with a turbo scavenged from an old Cat diesel. This inspired him to incorporate a similar setup into his drag car, a decision that has clearly paid off.
“With the desire to return to drag racing but limited funds, I chose to enhance the 300 six-cylinder engine on a budget,” Lopez shared in an email conversation.
The engine block dates back to 1965 and has been sleeved for added durability. Lopez managed to acquire a rare steel crankshaft from a local engine builder, paired with a set of robust Molnar connecting rods capable of withstanding forced induction. Utilizing old-school TRW pistons sourced from eBay, Lopez completed the lower end assembly. With its seven main caps, the Ford 300 engine is inherently suited for high power output applications.
The stock cylinder head remains in place, featuring a refined porting job for improved airflow. Secured by 7/16-inch ARP head studs, the engine internals have received significant attention from Lopez. He developed a custom cam synchronization system to complement the upgraded camshaft, enhanced the water outlets, and fabricated his own lifter cover. To ensure a proper seal, a set of Comp Cams valve springs and a Fel Pro 1024 head gasket were installed.
The power boost is enabled by an 80-millimeter VS Racing turbocharger. This appropriately sized unit has produced up to 43 psi of boost in Lopez’s Fairmont while offering rapid spooling characteristics. Fuel delivery is aided by an Accufab 75-millimeter throttle body, supplying the 210-pound injectors that are currently operating at their limit in this configuration.
Lopez admitted he never anticipated the Ford 300 engine to deliver such immense power. During the Rocky Mountain Race Week in June 2023, he achieved a 10.6-second quarter-mile run despite significant wheel spin, a result that astounded him.
“The issue arose due to the undersized injectors. Designed for 700 hp, I clearly underestimated the engine’s capabilities,” Lopez explained. “The following day, I drove the 3,300-pound wagon to Denver for a run at Bandimere, achieving a surprising 10.40 at an altitude of 9,000 feet.”
Following this breakthrough, Lopez estimated that the inline-six engine was producing between 600 and 700 hp at the crankshaft, prompting him to conduct a dynamometer test. The Fairmont registered the same power figures at the wheels through a Ford C6 transmission and a 9.5-inch ring gear. Accounting for drivetrain losses, they approximated the engine’s output at around 880 hp at the crankshaft.
on 32 pounds per square inch of boost.
During the next visit to the drag strip, the wagon effortlessly outpaced the truck in the adjacent lane. It dashed to a 9.65-second time covering the quarter-mile on that attempt, and following some fine-tuning adjustments, it finally achieved its best timing of 9.31 seconds. “The vehicle reached its maximum rpm before the halfway mark at 6,900 rpm and maintained a steady pace,” Lopez recalls. “I anticipated that it would have delivered a high 8-second run by analyzing the stats at the halfway point. Consequently, we estimated that with an additional 10 pounds of boost, totaling over 1000 hp, we had generated an extra 200 horsepower.”
The forthcoming upgrades on the agenda include larger fuel injectors, enhanced gaskets, and o-rings to evaluate how the vehicle manages 50 pounds of boost—or possibly more—in the upcoming year.
“I’ve experimented with a wide range of engines over the years, and the 300 is truly surprising,” Lopez expresses. “It provides affordable, enjoyable horsepower that doesn’t necessitate wealth to achieve fast results.”
Isn’t it simply fantastic, everyone?
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