Hi, at the moment my 2005 WRX has a toyosport backbox on which is kind of on my limits for loudness. On Tuesday, I'm having a full de-cat system added which I know will increase the noise levels. I'm therefore tempted to put the STI backbox on that a friend has given me. Just a couple of questions I have are 1. How much will this affect the power once the de-cat had been installed and the remap has been done (will it be better or worse with the sti box over the toyosport box)?
2. How well will the sti backbox get on with a de-cat system in front of it (will it be too restricting, etc)?
Hope someone can help, like I said, I have until Tuesday to decide, and then on Thursday I'm getting Duncan out to remap it.

 

Hi there, the sti standard backbox will be restricted and not freeflowing how much of a restriction is anyone guess but a restriction is restriction.many say the aftermarket genome exhaust is restricted as it has a baffle in the centre.best exhaust will be prodrive back box

 

Full decat will increase exhaust sound dramatically even on the not so loud ones-prodrive,racebox genome toyosports.but generally these are accepted by many as perfect sounding exhaust systems not to loud but nice burble soundtrack

 

Thanks for the replys. Looks like I'll leave the toyosport on then. It does look good on the car.