Depends. On a completely stock car, yes, you would likely lose low end power and see minimal top end if any gains. However, throw in a nice CAI, and a completely aftermarket exhaust from the precats to the third cat, and a 3" exhaust would give some pretty nice gains. I would suggest buying the xlr8 J-pipe first
Yes, the XRL8 "Jpipe" will make a difference with the stock exhaust. Once you add a catback the gains will be better. However, if you are going with a 3" exhaust, you may want to look into either a 3" collector on the Jpipe or some type of venturi collector going from the 2.5" collector on the Jpipe to the 3" catback.
And yes a 3" catback is a good idea if you plan to do more mods.
1. crush or mandrel bends?
2. ss or aluminized piping?
3. whats your setup up front? pcd? hfpc? jpipe?
4. since you dont have hfp rear lip, should get the stock cap for the left side
5. not really digging the tip :/ is there a reason you went with that style?
oh and when you get a chance, please post pics from underneath
Hmm, I wonder if it would be possible to run a long resonator off the end of the JP, basically into one of those hushpower mufflers with a downturn, and then cut the stock midpipe off at the Y, and leave the stock mufflers hanging?
^^ I have a longgg resonator coming off the Jpipe so I wouldn't see why not. Well, after the custom collector I do. About 3 or 4 inches (from my recollection) after the merge collector I have a Magnaflow 6in round by 30in long muffler. It deadens the sound pretty well, but I'm still loud as fcuk. I have a feeling my mufflers are starting to blow out, but I'm not 100% sure.
If you ran a downturn after a large muffler it would probably be pretty loud when coupled with the PCDs, unless you went with a large rectangular muffler. They have a few: 5x8x18, 5x8x24, etc. All I know is, with my exhaust disconnected at the Y, meaning the long Mag is the only muffler doing any 'deadening,' it was like running open Jpipe with the stock cats.
About a year or two ago before I started modding my car, I was able to get a ride in a member's car. I don't remember his name on here but he had a black 7.5 gen sedan with the coupe hood. He was lowered on D2 Racing Coilovers and had the neochrome wheels, I don't remember which one though. I remember he had a full 3" exhaust and a HKS Carbon-Ti muffler at the end. It was also a single exit. No other restrictions that I can remember. It sounded mean! I loved it and ever since I heard it I have always wanted to do the same. I don't remember if there was a J-pipe or not.
This is probably going to sound like a dumb question, but the y-pipe that Magnaflow makes can be mounted either way, right? They always say the dual side is the inlet, and the larger, single side is the outlet, but I can use it the opposite and run a large midpipe to it with two smaller pipes to each muffler, right?