4 into 1 Exhaust 0-320 D3G ?

[ratc]

Have any -4 builders found a good source for a 4 into 1 exhaust system ?

I've spoken to Larry Vetterman recently, it's something he would rather not undertake since he feels the gains (if any) are marginal set against the basic 4 pipe.

It's still an option I'd like to look at if anyone has any info.

Thank you in advance.