Catalina 30 Muffler

[Merino]

Ok... so I have a 1979 Catalina 30 with our beloved atomic 4... Unfortunately a leak developed in the exhaust manifold (confirmed during rebuild) which started the dreaded stuck valve syndrome which lead to one of the cylinders becoming frozen... So my atomic 4 is currently being rebuilt... Since the engine is out and I'm trying to optimize things while engine is out (lots of room to work). My original Catalina 30 muffler intake is damaged (crushed) and I intend to replace it... Started to look around and realized that most of the waterlift mufflers I've seen seem to be much smaller volume than my original (except the one offered by CatalinaDirect which is larger). So given that this is a Catalina 30 with the known exhaust issues (limited space, possible backflow when heeling), should I be concerned about the volume of the muffler?

Thanks,

Dan