Borla exhaust drone

[donny]

Over the Easter weekend we took a 500 mile road trip. On the roads where 70 mph was the speed (freeways), there was quite a hum or drone from the exhaust. I called Borla and they said they had a venturi that could be installed in the pipe. They sent it free and I tack welded it in last Saturday. It really works. It cut the hum by half. I'll keep everyone posted because they sent two venturi's if the first was not enough.

[Toad Boy]

How does that help? It sounds like a restriction which limits the free flow of gas which was the point of the system.

When I called Borla they said the venturi would change how the exhaust flows but not restrict it. Venturis have been discussed at some length regarding intake systems on this board. This part is about 2 inches long and the same diameter as the inside of the exhaust pipe then it necks down about 1/4 inch less for about 1 and 1/2 inches then back to the inside pipe diameter again.
Donny