Well, let's see ... it's a diesel @ approximately 1000 RPM ... I'd assume at least 50lb-ft of torque at that engine speed, which equates to about 9.5 horsepower ...
745.7 watts = 1 horsepower
9.5 horsepower = 7084 watts (At least !)
Then you take a speaker which is 51" in diameter (less the surround, of course, which looks to make it about 45" in diameter). This gives it approximately 10,000 square centimeters of cone area, which is roughly equivalent to 20 12" subwoofers ...
Then consider the fact that it looks to have about 4" of excursion each way judging by the crank ...
When you can displace 200 liters of air per cycle, it's not suprising that you can hit 160 dB //content.invisioncic.com/y282845/emoticons/tongue.gif.6130eb82179565f6db8d26d6001dcd24.gif
As for the record, no, it's not a record ... See RC's 6 foot sub //content.invisioncic.com/y282845/emoticons/tongue.gif.6130eb82179565f6db8d26d6001dcd24.gif Plus I'm pretty sure it would have to be electrically powered for it to be considered a record as well ...