Billy Boats from what I have heard are the deepest by far for these "exotic" sounding trucks. I love mine, it kicks some serious ass. All Billy Boat: Long tube headers (custom fit/altered RH/drivers header), Catless mids, Catback system. While the Batram was getting it's wheel alignment I asked the guy there to test the noise volume, here are the results, louder than I thought.
Idle = 85db
3,000rpm = 102db
4,500rpm (backing off/popping peak) = 116db
We estimate that it will be close to around
118-120db at red line or shift point 5,500rpm. All testing was done as per NZ regulations, 2 metres from tips in an outside environment. Seat of the pants driving around the city is pretty quiet for what it is, sure you can hear it but it's not in your face. No different to a mild V8 modern and/or muscle car, it's fantastic. Step into it and watch your penis and smile grow bwhahahaha!!
On another interesting note. I have spoken to 2 different Billy Boat tech guys and emailed 1 and all of them have said, convincingly, that the noise volume difference between hi-flow and catless mids is
ZERO. They said that I wouldn't be able to hear the difference, they are around the same db readings, no difference at all. I was shocked as straight through pipes are usually ALWAYS louder so I doubled checked each time, same answer. They said the only reason to go with hi-flows is if you need them by law other wise go catless 100%. Must be true, they would know and the catless pipes are like $150 and the hi-flows are like $660+, if anything, they'd be wanting to sell hi-flows and talk them up. This maybe at idle and low rpm driving though. Still.....if it's loud, clutch in past the fluff......all good lol. :laugh:
Cheers,
Carl