I honestly can't remember where or when, but I remember coming across some people saying that the Stillen exhausts didn't yield much, if at all any, hp gains; merely a change in exhaust note. Can anyone confirm? Sure...an exhaust system isn't going to yield much, but from what I've heard, Stillen exhausts for the G37's yield...next to nothing? Thanks in advanced fellas!

Eric

PS Invidia Q300's or Stillens? I think the Stillens look much better (+ AutoX Diffuser).

 

Any bolt on exhaust is going to have very limited (ie next to nothing) gains until it's tuned. That is where 99% of bolt on mods get their power from, is the tuning.

 

I don't know the specs or numbers, but I do know this: Air = HP. It stands to reason that if you do an intake and exhaust, together, you should get better air flow in and out, increasing HP. IF (big if) the JWI claims of 6-10 whp are true, I don't think it's out of the question to get 15-20 hp doing an intake and high flow exhaust.

As an aside... I put a JWI and Stillen exhaust on my '04 G35 sedan and didn't notice much difference at all (but it sounded sweet). When I decide to upgrade my '11's exhaust, I won't be using Stillen again.

 

Yes Air=HP. But the computer is what controls the air getting in your motor, not your intake. Unless you do a tune, bolt on modifications will yeild almost 0 gains (In some cases it actually produces negative gains)

 

^ yeah, i figured something along the lines. i do plan on doing minimal bolt ons - intakes, exhaust, and hfc/test pipes. + osiris.

@mac - why no Stillens? just wondering...

 

I had the stillen CBE installed with by SC installatin and tune. I can't tell you whether the exhaust itself contributed to the gains but I really like the sound and it looks good IMHO. It is not overly loud and has a nice agressive tone at WOT. Just what I was looking for.

 

I went to lesser priced system that looks 1000 times better IMO Exoticspeed RT-2 PWR.

 

i dont why everyone is saying you get next to nothing by putting bolt ons on your.all i have are bolt ons on my car without a tune and there is a difference in power.. all a tune is going to do is put your A/F ratio back to where it should be and your going gain more power out of that..

 

So if I put an intake on and an exhaust on... then I have to "tune" it? What does that consist of? Will the car's cpu not make adjustments based on the higher flow of air?

What, exactly, do the mechanics do when they "tune" it?

 

I had the CBE on my 04 G and noticed zero difference in power but it did sound good. I want the power... sound be damned!

 

Just go ark! Can't go wrong

 

Except, the biggest choke point, the catalytic converters, are still there.

Air can only flow as fast as the point of highest restriction allows it to flow.

 

Mike, why are you still posting on intake and exhuast threads?...you're better than that...

 

Because I just spent the whole farking day dynoing.

10am to 10pm.

And slightly grumpy after hearing loud cars and breathing exhaust fumes all day. And, I'm supposed to be instructing at the track tomorrow. Not sure why I'm awake.


Oh, and my exhaust's primary purpose is to reduce weight, rather than gain power. Heh.

I will now recuse myself from this thread.

 

I can't say what power increase I gained from the CB exhaust because I did the whole CAI and tune at the same time. Just don't rule out the Stillen exhaust because of gains or lack thereof. It's flow, sound and looks are positive IMHO. Nothing against Fast Intentions and Ark. They are great too! It's all in what you are looking for. I got my setup from Stollen because they are close, they were reputable (I thought), and because I figured they would have designed the CAI and CBE to flow as one system. I actually have no clue if they did or not. They don't participate much on this Forum anymore.