Geddon

I'm a little confused about the sizes quoted for exhausts.
Does a 3.5" tailpipe refer to internal or external diameter?

I currently have a prodrive backbox which measures 3.5" external but 1.75" internal in the perforated tube. I also have magnex d/p and centre decatted and feel the backbox is restrictive plus it has started making whistling noises.

I'm looking at getting another (preferably magnex) but am confused as to which one? Is it the restriction in the prodrive one the problem or the size?
For instance would a Magnex 3.5" be better- ie by being straight through? Or do I need bigger?

Also do all the aftermarket backboxes come with removable baffles or not?- can't seem to find any info on this. Would prefer a baffle option for when I fancy a quiet time or for trackdays etc.

Does anyone know if the magnex backboxes come with removable baffles?

Geddon

anyone?

Jolly Green Monster

iTrader: (4)

tail pipe size only..

basic pipework sizes are 2.5inch (standard) and 3inch, APS do a 3.5inch system, if you are lucky the internal diameter matches the pipework.

As you are only looking at replacing the back box you need a normal 2.5inch one anyway.

Magnex to my knowledge doesn't have a removable baffle, but should be less restrictive (little bit) than current back box. Most do not have removable baffles except Blitz Nur Spec, HKS Hyper for example.

Simon

Geddon

Thanks for that
So what is the internal diameter of the magnex backbox?

Jolly Green Monster

iTrader: (4)

no idea..