I've got a Powerflow system on mine Mike and from what I could see of the tiny pic on my screen, your backbox looks very similar size to mine!
I just have the back box, no centre section.... I'll try to find some vids of how loud it is. Obviously it'll be different on a petrol, but just as an idea!
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I just have the back box, no centre section.... I'll try to find some vids of how loud it is. Obviously it'll be different on a petrol, but just as an idea!