Ever seen inside a Prodrive backbox? Take a look...
 

A little backstory. This is the original Prodrive exhaust recently removed from my Blob STi PPP. Upon taking the exhaust off the car, and cleaning it up a little, I was greeted with this:

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A nice big hole and an attempt to cover it up! :wonder:

So being the inquisitive fella I am, I had to take the plate off and take a peek inside (after stripping every screw head and resorting to blunt force):

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Just a single, perforated pipe.

Now I'm not a technical guy, but I can only assume that perhaps there was once a packing material in here to help muffle the sound?

So this got me thinking. For a bit of fun, now that there's a gaping hole in my spare backbox, is there any way I can try to alter the sound?

Just a couple of ideas:

• Sleeve the perforated inner pipe with a sheet of aluminium, clamp it on and effectively have a 'straight through' backbox?
• Tightly pack the chamber with material and have a makeshift 'Glasspack' exhaust?

Would this make any difference at all? I'm thinking not much - but is it something worth trying?

Buy some exaust turbo whistles and put a few in there, would be good to see how it sounds :D lol

http://m.ebay.co.uk/itm/131103369294?nav=SEARCH

Hmmm, interesting, wouldn't bother with straight threw.

If you covered up some of the holes may give a deeper sound

I think that box has been cut open and had the sound deadening removed. So no a true likeness of the inside of a prodrive box.

Wadding

Oh god, I don't think I could bring myself to do it.

Is that a fact? I'm trying to visualise how the muffler chamber alters the sound but I'm clueless.

I bought and fitted a TSL Group N backbox to my car to replace this, but at the moment I'm a little disappointed with it. This is more than likely because this Prodrive exhaust was already louder than it was supposed to be with the wadding material removed.

That is proper pikey lol :lol1:

Tell me about it, I was gutted when I took it off the car - was hoping to sell it on, but no chance of that!

Oh dear! that is a gash job.