alosirgal

Hello,

I recently bought the Top Speed Pro-1 exhaust system
https://www.ebay.com/itm/Fits-Infiniti-G35-G37-Sedan-07-14-Top-Speed-Pro-1-Y-pipe-Back-Exhaust-System/372107865994?ssPageName=STRK%3AMEBIDX%3AIT&_trksid =p2057872.m2749.l2648

I'm new to the car scene and stuff so I have no clue what the names are on some parts and since the exhaust system that I just bought isn't a "complete exhaust system", is there an aftermarket part(that would maybe do more than a stock) for the "other" ypipe near the front(i believe its closes to the catalyc? converter)

Thanks in advance!
Edit: My car's a '10 G37X Sedan

blnewt

iTrader: (13)

Replacing the stock Y-pipe w/ a larger less restrictive Y-pipe doesn't match evenly w/ the Top Speed flanges, it's larger so there's an abrupt change, in piping rather than a smooth transition, this will introduce rasp and cheapen the exhaust note rather than enhance it.
I would keep the OEM Y-pipe but change out your OEM cats to Resonated High Flow Cats or resonated test pipes if you live in a state that that doesn't have tight emission checks.

alosirgal

What's the difference between the two? like how will they affect my exhaust(note/sound or what not)?

blnewt

iTrader: (13)

It will up the volume a bit, not obnoxious at all. Test pipes will emit a raw fuel smell since they don't have a catalyst though, so if you spend a lot of time in stop & go traffic w/ the windows down you may notice it. Also some models don't have very good o2 ports so you may get a check engine light. I would recommend Fast Intentions, they have an o2 port that won't throw a CEL, and are high quality parts.