Sounds quite nice that mate. I would disagree with feeling a performance increase though as backbox wouldn't add any bhp really and if so it would be negligable (like 0.1-0.5hp or something). It will just be the sound that makes you think its quicker but actually isn't. Does sound quite nice though to be fair. What make is it?
If you want performance, stick a 4-2-1, full system and induction kit. I definitely felt a difference with the 4-2-1 and full system on mine. With the mods I mentioned above you should see an extra 10-15bhp depending on what you get!
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