This past friday I decided to bite the bullet and do something that I'd been thinking about for the last couple of weeks: have an exhaust shop weld a custom h-pipe into my Injen SES straight-tip exhaust. Seeing as how the Injen is the only true dual exhaust to not utilize an h-pipe, I thought that maybe there was something to this. So off I went to visit a local exhaust hillbilly. A half hour and $40 later, I had an h-pipe located just before the resonators in my exhaust. I left the shop eager to see how it sounded.

The overall volume of the Injen was lowered slightly, but is still most definitely an attention-getter. The h-pipe accomplished the two things I was hoping that it would do. First of all, the drone that was oh-so-noticable on the highway between 60-65 mph was definitely improved. Not gone, but much more liveable. Secondly, the exhaust regained some of that characteristic "Z" sound that we all know and love I was very happy about this, because although I loved the aggressive sound of the Injen, I also missed the unique howl of the Z. The h-pipe also introduced a cool-sounding gurgle, almost V8-esque, around 2500-3000 RPM when cruising around town, which is definitely a +.

Performance-wise, I couldn't really tell a difference, but for me, this was more of a sound experiment anyway. Overall, I think it was worth the $40 spent to have the exhaust sound how it does.

Unfortunately, I also installed Helix test pipes later that night (thanks to one350zfan for the use of his garage and his assistance!). I am pretty disappointed in how my exhaust sounds after putting them on. It sound really mean when cruising around, but is VERY loud, almost unbearable drone on the highway, and at WOT, sounds like garbage due to the hissing / rattling noise that everyone with test pipes experiences. The Z does pull more up top however.

I will now be hunting for some Stillen Race Pipes to replaces the Helix's after hearing one350zfan's Z with the Stillen / Injen setup. Very mean, and not TOO loud.

So overall, h-pipe = , and Helix TP's =

 

Its difficult to tweak an exhaust system in search of a specific sound. If you think that the Injen Super SES Cat-Back Exhaust System is loud, wait until after you get headers.

 

stillen is going to sound the same...get some resonated test pipes...

 

Wanna bet! I was standing next to the car and it doesn't sound like mine(Ingen/StillenTP). Resonated pipes will give him rasp IMO. His car didn't sound bad to me but it was in my garage(with an echo) and I didn't test ride with him. He rode in my car earlier that evening so he knows what to get to achieve the sound he's looking for. I hope he goes with stillen TP's so I will know if his custom H-pipe reduced that low RPM drone.

 

Do you have any sound clips of your modified injen exhaust? I have one for my g35 coupe and I was thinking of doing the same thing, but just wanted to be really sure.

 

Clicky I took these really quick- Also have cats and top speed headers.
http://www.yourfilehost.com/media.ph...e=MVI_0086.avi

 

link isn't working. keeps freezing.

 

Get resonated test-pipes, problem solved. Shoulda done more research and not even tried non resonated with the Injen-thats one of the loudest combos out, not for everyone, although I sure loved it.

 

http://s6.yousendit.com/d.aspx?id=0I...429QO78V29U01A

new link. I'll try to take some better ones if you want.

 

Thankx for the clips. Could you get some more if you don't mind? Also would you agree with the first post about the changes the h-pipe made? I contacted a local shop if they could do it and they gave me a quote for 200 plus materials . I need to find a shop like the first post.

 

Yea I'd have to agree on the first post. The "H" pipe made the exhaust sound better and help take some drone away. I'll try to get some good clips soon. Yea def. find a cheaper place i only paid 30$.