Classic Chambered

[Clayboy]

Nick,
Thanks for the explanation and congratulations on the 5K milestone.
Bob

[Rare Iron]

Personally, I don't think you gain anything with a 3" flowpath muffler unless your engine is putting out over 480 or so HP. You can lose flow velocity on a gas engine when the exhaust system diameter is too large - opposite is generally true with a diesel. Any other V-8 Cobra system 2.5" should be optimum diameter.

Also, statistically probably 97% of all the Cobrapacks I build & sell are with packing material to absorb the sound. All the 3" core mufflers are going to be loud & deep, but with packing will absorb dBA's & not hurt the flow any. The packing will definitely help soften the noise some.

[mickmate]

Hey Eric what's your thoughts on the effects of louver direction on noise and performance with your Cobrapacks?

[Rare Iron]

Over the louvers or WITH the grain (not my recommended flow direction) still sounds good, but at least 4 dBA's louder - this info from several customers who have done this & measured the noise. The small louver pattern I use does not impede the flow very much - look at the performance reported by Kinetic & that was before I made them with a clean & consistent 3" flowpath. The ones they tested necked-down to 2.5" at the entry & exit of the 3" core - I build them differently now. Performance stats on the current design would be much better so there would not be much loss at all.