hi all,

needed to ask some qns regarding .12 pipes.
they come with 5.2, 6 and 7mm stingers.
i know legal pipes are 5.2mm.
but do the 6 and 7mm ones really make much more power?
which one makes low end and which one is for high speed?

i also know that the manifold plays a part, but assuming all other things equal, what's the diff btw 5.2, 6 and 7mm pipes?
and what about those 'turbo' pipes? are they using larger stingers?

let's say i need not conform to regulations, what wld be a gd pipe for my OSspeed 12TZ?
i'm looking at OSspeed T-1040SC 6mm and ZAC kawahara 6mm.
sumone did mention to get the mugen P01002 pipe (legal pipe?) supposedly works well with 12TZ series.

currently i have a ZAC 7mm. shld i stick wif it or get one wif a smaller stinger?
thanks in advance!
and waiting for replies from the engine gurus out there...