Why are Mopars so much louder than other brands with open headers?

[Ghoste]

I know on the surface this question seems like it belongs in another forum but I suspect the answer lies somewhere in this one.  Last night at a cruise event here in town, myself and a couple of friends opened our exhaust.  They both have VERY strong blue oval products and my car was far louder than theirs.  I've noticed this before at dragstrips and I just figured for sure one of the regular racers here would know the reason.   

[Nacho-RT74]

dunno really why, but is a fact that even with STOCK parts, Mopars are already louder

[Ghoste]

Would it have anything to do with flow velocity in the exhaust ports?

[Runner]

im really not sure they are louder.   i think it just depends on alot of things.   my buddy that passed away had a bb nova that ran 11.70s and its louder than my junk is when they are both uncapped. in fact im a little jelous of how good it sounds. 

[Silver R/T]

im really not sure they are louder.   i think it just depends on alot of things.   my buddy that passed away had a bb nova that ran 11.70s and its louder than my junk is when they are both uncapped. in fact im a little jelous of how good it sounds. 

exactly, depends if its big block/small block, what size headers, brand, equal length or not, etc.

[aifilaw]

The sound presentation is directly related to the velocity and inversely the static pressure in the open headers, followed by the resonance created by where it is piped out (hall effect and echo)
The sound production is directly related to the cylinder volume, engine speed, valve speed, port velocity, et cetera.

In other words, chevy, ford, or chrysler. They call can be made to be as loud or quiet as you want with the right combo.

[Challenger340]

Camshaft is a factor also.

[morepower]

if your detonation is happenin in the exhaust your car will be louder also, usually louder cars are more out of tune.

[Ghoste]

It's in tune. 

[mally69]

 

[Mike DC]

It's sorta like asking why one chick looks so much better in the same cutoff shorts than another one does. 

[Rolling_Thunder]

I dont know man...      I've heard a 426 Hemi with open exhaust and it was not as loud as my friend;s father's BOSS 429 with open headers     

[Ghoste]

That's interesting, were they both stock?  The guys Fords that made me first post this are both FE engines (428 SCJ in both), but it has also seemed to me like big block Chevy's are not real loud.

[Rolling_Thunder]

That's interesting, were they both stock?  The guys Fords that made me first post this are both FE engines (428 SCJ in both), but it has also seemed to me like big block Chevy's are not real loud.

yep - both stock....    the 429 sounded BAD ASS...           but this was a street hemi...      i'm sure a Race Hemi would have been different