I don't know if anyone has done it but has anyone installed a jpipe with the stock exhaust system? Just curious if the sound changes at all. I spoke with a rep from XLR8 and there in the process of making an exh sys for the base 4g so I have to wait a few.

 

generally speaking; it changes the tone...but does not get louder.

this is what I experienced on my 3G TL.
which is fairly the same as the 4G.

the tone will change,a deeper sound, but will stay at the same decibel while idling.

when at WOT; it sounds akin to an aftermarket cold air intake...a rush of air

 

can you feel the power gain?

 

generally speaking; it takes about 30hp to feel in a 3500lb car.

 

OK thanks I'm just hoping the exhaust system comes out soon. Ever since I got this car I've had the mod bug

 

Well done Justin.

 

Thanks for the helpful info, considering I'm currently looking into a j pipe right now!

 

I just put on the Jpipe and a HFC with the rest of the system remaining stock. I do not have an intake, but do have the intake resonator removed on a 4G SH-AWD. I will say there is definitely a difference in tone from 2000-2500 RPMS. Some would say it is similar to a drone sound but I don't think it is. Also between the 4000-5500 or so RPM range it sounds similar to a quiet VQ engine sound (Infiniti). If any of you guys had the 3G with the mid-muffler removed it sounds very similar.

The one performance addition I can tell is the 65-85 highway pass is easier without downshifting (6MT). The auto may be different and the base may be different as well. Hope that helps!

 

Our XLR8 V1 j-pipe doesn't remove a cat so the exhaust note should be the same. The V2 j-pipe eliminates the third cat so the exhaust note will be a bit more aggressive.