Does anyone know what or if there are any specific codes for Big Port Heads? I've had a look around and it appears that heads starting with RHT and LHT (maybe V8) are definitely big port heads but I've also seen on a few other places that heads starting with RHS20V and LHS20V are also big port but opinions differ!

I had heads starting with RHH on my bug which I think were 2.5 heads but have aqquired some replacement heads that have rhs20v and lhs20v on them..... there is a massive difference in the intake ports.....

RHH head intake ports


RHS20V & LHS20V head intake ports


Any ideas!?! Just trying to firm up what heads I have!