Exhaust back box

[big_treacle]

Morning all. Are the 4.5 & 4.2 backbox the same? I.e. can I stick a 4.2 one on my 4.5 or are they not interchangeable?

Cheers

[Cyclone1]

4.2 pipe circumference on std systems and some sports replacements can be smaller than that of a 4.5, so check to be sure.

Jules.

[big_treacle]

Cyclone1 said:

4.2 pipe circumference on std systems and some sports replacements can be smaller than that of a 4.5, so check to be sure.

Jules.

OK cheers. I knew it wouldn't be simple

[M3John]

Mine fits just fine. Standard 4.2 all the way to the manifolds.

[big_treacle]

Will a Speed Six back box fit a 4.5? Or is it completely different? Cheers

[Pursyluv]

Are you after the standard TVR back box or an aftermarket type?

[Tanguero]

The Speed 6 back box has both different size pipes and they are spaced differently. It can be made to fit (I did it) but you need two adaptor pipes that change diameter to take up the extra length required, and fiddle with the intermediate pipes to get the offset right.

As I picked up a 99p S6 box from ebay it was worth getting it right, but it did take some time and fiddling to make everything line up.

[big_treacle]

I was looking at a standard one but I think I'm gonna have to just get an aftermarket replacement.
Thanks for the S6 info, cheers.

[Cyclone1]

If it's just a back box then I'd recommend just getting one fabricated to your spec (plenty of places about to do this). It won't be too expensive and will give you something unique...

Jules.