The big long 300 can make monstrous torque. It will also keep on running long after that Maverick is a pile of rusted parts with minimal care. All of those positives may not out weigh the negatives of a really long and heavy crank that means the 300 I6 doesn't rev as readily as other motors. It's also cast iron and if memory serves the same weight as the 302 V8.
Now, the Aussie's are still using that motor in some serious applications. They've updated the head, intake, and exhaust side. They've turbocharged it and turned the motor in a monster. Numbers like 362 hp and close to 400 ft lbs of torque were produced via factory motors. Citation needed you said? Ok. I got a page right here.
The last paragraph on that page reads:
The Ford Inline six in racingThe Ford Inline six has had a small though colorful career in racing, which has increased in recent years due to the rising popularity of the motor and the availability of performance parts. The big 240's and 300's offered stronger torque at lower engine speed than most V8's of comparable displacement, while sacrificing peak power because of their square bore/stroke. The long stroke combined with the longer crankshaft creates problems at higher engine speed, and most stock cast iron pieces are not recommended for service above 5000 rpm. The engine also weighs more than a V8 of similar displacement due to the longer length. The most desirable engines are those from mid-1960s dump trucks, as they have forged steel crankshafts and high-flow exhaust manifolds.[1]
A recent yet giant step in Ford Inline six racing has been performed by McLearran Motorsports in Tucson AZ. The McLearrans, Wil and Kelly, have achieved enough notice that their 1963 Ford Falcon has been seen in several magazines and was scheduled to make an appearance on the show Pinks.
The 1963 Falcon driven by McLearran Motorsports' Kelly McLearran has been dyno tested at 323 rwhp @ 4500 rpm and 502 rwtq @ 2650 rpm. The car has run a best time of 10.89 seconds at 1/4 mile, with Kelly driving.
