Hi,

Does anybody know if fitting a standard STi back box to a MY03 WRX gives any performance increase?

I'm guessing that it'll give better gas flow than the standard WRX twin tail pipe. I want to keep my warranty/neighbours, so I'm looking at standard parts only

Cheers.

 

If you want 'standard' parts,then if I were you,I'd buy a WR Sport backbox rather than an STi one.I doubt you'll find any performance increase from an STi backbox but you will from a WR Sport one!! (Although not as much as a Scoobysport one for instance)
The STi backbox is mild steel (Same as the one you have now) whereas the WR Sport is stainless steel and therefore won't rust!!!
There was a WR Sport backbox for sale on here last week.Have a look in the for sale section!!

Good luck

Nick

P.S: I've run my car with both a WR Sport and Scoobysport backbox over the past couple of years (Eventually sold the WR Sport and still run mine with a Scoobysport system)

 

Scoobysport backbox for sale here - http://bbs.scoobynet.co.uk/showthread.php?t=343469

PPP backbox for sale here (Similar to WR Sport but with rounded tailpipe and not oval one) - http://bbs.scoobynet.co.uk/showthread.php?t=342677

WR Sport backbox - http://bbs.scoobynet.co.uk/showthread.php?t=342452

Should save you a few quid anyway (Don't buy these things brand new as the WR Sport bb's are £350 from your friendly dealer)

I'd keep your money in your *** pocket and not bother buying the STi backbox anyway!!!!!

 

Cheers Nick.