everyone says that glasspacks are very restrictive but the thrush glass packs (dynomax) have a perforated center tube and so do the dynomax bullets. why would they be restrictive?are they?
also i dont want cops on my *** all the time, are spirals quieter than bullets?

 

i have the spirals.....and yes they're quieter.....not by much....and we're still talking LOUD very very LOUD.

 

perf. core glasspacks aren't as restrictive as the old school ones, they would flow ok, but sound like a dump truck at WOT. The bullets are louder, but have a larger ID core than all the glasspacks i've seen.

 

ok, well does anyone have the cfm on a 2.5" in/out thrush magnum? im leaning towards these for my set up.