I have searched and searched and searched. All I have found is opinions. Opinions are great, but I'm looking for facts.

I don't care what the exhaust looks like.
I don't care what the exhaust sounds like.
I just want the one that produces the most power, N/A, as a standalone mod. I cannot replace my cats, but I can replace the y-pipe.

So, anyone with facts, dynos, ect. Please assist me i finding the best power making exhaust. Again, it will be my only power modification.

The answers I have seen in the past are:

Stillen Single
AAM single
Injen SES (i have reservations about this one)

TIA

 

I think the single exhausts are the best power adders. I had dual before but I now have the Agency Power single, and it makes a world of difference. Plus, the exhaust system is lighter.

The singles exhausts I know of are; JIC, AAM, Agency Power.

 

Has anyone had experience and/or dyno'd with the Agency Power piece? Thanks

 

I believe there was a shoot out a while back on the borla,nismo, and hks. I forget which one made the most HP. I think it was borla, but it made second in torque. I'm sure someone else will chime in later.

 

I might dyno mine in a few weeks. I can tell you this much though. My old setup was test pipes, true dual exhaust, intake vs now which is just the agency power y-pipe back and the Z pulls harder than before.

The only drawback is the fitment isn't dead on and it's very loud.

 

The shoot-out is published by Sport-Z magazine. Its several years old, but still valid.

 

Damn, you posted right before me. Thanks for the information. If you do dyno, please let me know!

does your Agency power exhaust have a resonator in it? The one I'm looking at does not. However the Topspeed pro-1 exhaust I currently have is LOUD and it would be hard to believe that the AP exhaust is equal or louder.....

Do you know how much the AP exhaust weighs? The AAM is 21.5 pounds from y-back. Thanks!

 

I appreciate the information, however those three exhausts are not on my list at all. Nismo is too heavy and power weak, borla is too weak, and the HKS is too $ for WIW

 

The AP doesn't have a silencer which makes it quite loud. The weight I would say is light. The piping is SS, but the canister is all Ti. I'm not sure if the AAM single is all titanium, but my exhaust is definitely less than 21.5 lbs. I just wish it was cat-back.

 

Why do you wish it was cat-back, if you are experiencing better gains than you did with the y-pipe and true duals? How big is the piping? I would assume that it's 2.5" as you are using the stock y-pipe, right?

What fitment issues are you speaking of? I know there is no silencers with the exhaust, but no resonators too, right?

The Pro-1 I have, even with the silencers in, is the loudest full exhaust I've ever heard.

I dont' really care about the noise though, as long as it creates the most power.

I'm surprised that there's not more responses! I find it quite pathetic that people spend so much $ on an exhaust, just for sound or looks.

 

Just looking at the stock y-pipe makes me sick. lol

The piping on the AP is 3" with no resonator and no silencer. It sounds really good though mainly because of the titanium muffler.

I'd like to see how much more power it'll make with a aftermarket y-pipe. The true duals I had were quite heavy.

The reason why you don't hear much about AP is because the exhaust was discontinued for fitment issues. They are creating a new exhaust for the Z which will be out in March 07.

 

Yeah I thought INJEN won....

 

So you have the 3" piping on the AP exhaust, connected to the stock opening of 2.5" on the y-pipe? I'm amazed that that would make power!!

What are the fitment issues?

As for Injen, based on this, I would never buy one:
http://www.hypersprite.com/auto/pict...d002/injen.asp

 

Yes the stock y-pipe outlet is very small compared to the 3" AP piping. The fitment issues are mostly the piping being too close to the diff. and the front piping being too close to the bracket underneath the y-pipe.

 

So..... explain to me how you make any power with a 2.3" connecting to a 3"????

I have an aftermarket y-pipe that has a 3" opening....but you claimed that your exhaust, mismatched, makes more power than your test pipes, y-pipe, and true duals. It's just not adding up......

Do you have a lot of knocking noise from the exhaust hitting the diff and the bracket?

 

You will lose power if you go from 3" to a 2.3" not the other way around. I don't know how I make more power, but I definitely feel torque. Maybe thats because with tp's you add some top end but lose that low end torque. Another reason is the true dual exhaust is heavy, and has quite a few bends. The AP exhaust doesnt really have any bends, it's very straight through.

And yes, I hear the knocking usually when its in gear and I lift off the throttle. Or when I go into reverse.

 

A few things.
You can't tell me that a 2.3" connecting to a 3" won't lose power. Unless there is some kind of graduated piping, then it is just wrong. I'll wait until I see a dyno to set anything in stone, but I certainly don't want an exhaust that knocks into anything, and I would never run mismatched piping. Also, a dual exhaust, will not make you lose power because of weight. Being that the weight removed is below the center of gravity, even an argument that the 20 pounds you are losing can't be substantial.

So, I guess my search re-beings. The AP exhaust has now been eliminated.

Someone prove to me why I shouldn't buy the AAM single. What makes more power?

Cheers~

 

I'm not trying to convince you to buy the AP exhaust. Actually you can't buy it even if you tried. They do not produce them anymore.

Next, the exhaust would make more power if it was coupled to a 3" outlet y-pipe that is correct. But I am not losing power by having it go from 2.3" to 3".

Also the weight issue, my greddy evo2's were heavy. They were more than 20 lbs over the AP. I'm not here to prove anything but if I were you, I would either get the JIC single or the AAM. The single exhausts are easier to install plus you save a lot on weight.

Plus i've ran people with more mods and we're neck and neck. That should say a lot.

 

I just received a PM from you asking about my mods and my time and I responded.

Here's my take on it. I had the Pro-1 exhaust (inlet of 3") attached to my stock y-pipe (which I thought had an outlet of 2.5"). You can definitely make a little bit more power if you had 3" outlet for the y-pipe, but I don't think you'd lose any power (you just make less). As for the exhausts, they're all pretty subjective when it comes to how much they add. They all give about the same and the few whp diff won't do much for you. The single exit exhausts that I've seen don't make more horsepower than true duals or even dual exits. However, they are lighter so maybe that's why people get them.

 

How do you know the borla is too weak if you haven't been able to find any quantitative information?

The Sport-Z shootout had it as generating the most whp of those tested and even though it's dual, it still manages to weigh about 11lbs less than stock.