That's the Biggest problem that people don't understand about why a 3.8 (which was based on the 215 Buick). (and 4.3 for that matter as far as raspyness) sound so raspy is the pulses are not evenly spaced since the rod journals are split. This is what gives the raspyness to the sound. I have heard people say that splitting the exhaust into different banks will help, it will not it won't make any difference. I used to have people tell me that running a 350 with single exhaust would make it sound like crap and would sound "twice as fast since both banks are fed into 1 pipe" This was even in a car rag (Hotrod, Car Craft one of those) and I was running a Torque Technologies 3" exhaust system but I only ran the right side through a single 3" 3 chamber flowmaster it sounded just like any other 350 out there with dual exhaust. I also added later an Edelbrock TES system that mated to the same system and other than the normal header ping you get it sounded just like any other V8.
The piping isn't going to make any difference with the exception of adding a Helmoltz resonator which is application specific and requires a hell of a lot of math or Dumb Luck to make work properly. The original dual exhaust straight pipe sound clip is only because of the bends and the primary length being more equal. There are also several bends that are in there that we cannot see, I can still hear the rasp, though it's not nearly as bad as these cars sound.
Originally Posted by J57ltr
