Ege, do have experiance with HKS and heard the sound of it...?! As i'm more of the low torque guy.
What is your opinion with my engine setup...??
You told me about the dual system,but with this mod i just want to buy a bolt on system i think.
The guys from HKS aren't stupid you'd think....why would they keep the stock size diameter then....?! Just to change the sound with no HP gain...?!
I'm pretty sure that it has good gains. On that post, I meant using a 3.0" system vs a 2.5" system with aftermarket mufflers in both shouldn't make a significant difference on the top end. I honestly don't think the 35 engine (45 is another story) would fill a 3.0" pipe setup completely.
What I believe is that, from Y-pipe back there's not that many (and significant) restrictions except the oem mufflers. Replace the mufflers, though, you'll have a change in sound. IMO, HKS Legamax is as close as you could get to the oem in an aftermarket system. INFX35 has it and if I remember correctly, it makes a change in sound tone (not deepness, it's definitely deeper) after 4000 rpms. I think it'd complete your system pretty good. Just don't change your cats with test pipes.
Also, it's a 2.5" single system so you shouldn't feel any torque loss in the low range. Contact INFX35 for more details..
One more point: My gf says even with my APS setup, the FX sound is not completely gone. It definitely stays in normal driving but not when you start or when you go WOT.