I am looking for any 3" duel exhaust systems out there for a turbo setup. Any suggestions? Thanks, Rich

 

SFR makes the 3 inch dual piping with the HKS mufflers.

 

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http://www.website.com.au/350z/monster/exhaust.htm

Replace "website" with "airpowersystems"

 

Let me work my magic:

Abracadabra

 

Are you going for a lot of power like 600+ RWHP? if not 2.5 is better.

 

SFR and APS have 3" true dual exhaust, although the APS is not yet available. A few members here, including me, have gone with a custom 3" true dual. PM me your email address if you would like a vid of the exhaust.

Once I get the rear bumper installed (car is in the bodyshop now) you won't see the gap between the mufflers.

 

I am at 443rwhp right now with stock exhaust. I was hoping to get an exhaust that looked more like stock but flowed very well.

 

I'm pretty sure you are going to be hard pressed to find something like that with 3" dual piping. Most would probably agree that dual 3" with straight through mufflers and resonators is the way to go, both because of convienience and availability.

 

Rich,

Where in Sarasota are you and what TT kit do you have? I haven't seen any other turbos down here.... We should run..I'd like to see how my single puts up against the TT...

 

Your best bet would be to get the APS 2.5" true dual. It flows well and looks stock.

 

Why would the 2.5 exhaust work better than a 3" exhaust? I thought the idea was to eliminate back pressure. I am no expert!

Zman1910, I am at Fruitville Rd. & I-75. I have the Greddy kit

 

2.5 " exhaust will not flow better than a 3". Now dont jump the gun yet, hear out my reasoning.

For the most part most TT setups here are at 400 +/- a few hp with stock internals. We have a v6 with a 3.5L setup. Half is 1.75L.

Lets say we are making 500 HP at the crank. So we now have 250hp being made per each bank persay. So you have a 3cyl engine that is 1.75L making 250hp. You will not come close to maxing out a 2.5" diameter piping with that setup.

I know on a turbo car you have heard that the bigger the better for a turbo . WOuld you put a 4 or 5" dual exhaust on your TT z? Why not? See where im going with this.

3" will just add more expense (more material) and more weight. Honestly, you will not see any significant between a 2.5" and a 3", the only difference you will see is in sound. It will be louder and you will have a more tendency to get drone if not dont correctly.

my .02 cents.

 

You have to find the right balance. You do want to eliminate the back pressure so the exhaust can scavenge the gases from the engine but if you open it up too much the air slows down too much and cools therefore becomes denser and you lose performance. As a rule of thumb a 2.5" dual is good for up to around 500-600 and above that you want to go to 3"

 

Westpack you hit it on the money buddy. 3" duals is overkill. I respectfully disagree with you though about the air cooling down and becoming densor. Well you are correct that when air cools down it does become densor, but the key here is volume.

An ideal Exhaust for a turbo would be shapped like a funnel. YOu want it big up front and tappering down at the end. WHen the exhaust comes out of the turbo, it is at its hottest. As we know when air is hot it expands and when it gets cold it contracts. So when the exhaust comes out of the turbo its super hot and would prefer more space, as the exhaust cools down, it does not require as much space.

I can show it another way. WHen i took earth science back in JR HS when i had a crush on my science teacher ( ), the teacher had a ball and a ring. The ball fit in the ring with no problems. WHen the ball was heated up, it would not fit in the ring. I needed a bigger ring. I guess you can use this as a comparison. The mass of the ball did not change, the volume did though.

 

Another thing to remember is that guys that have been in the mid 500's have been having overheating problems, although I don't think any of them actually had a true dual 2.5" exhaust. I have 543whp and with a 3" true dual, I have never had any overheating issues and believe me I beat the chit out of my car everyday as it is my daily driver. I spend at least $15-$25 a day on gas and my drive to work is only 60 miles roundtrip (just to give you an idea of how much I beat it).

Here an example of how the bigger exhaust helps with cooling.

 

Yeah everything being said even though I say 3" is overkill that is what I am getting for mine I need a dual anyway and I am thinking of the future so I went ahead and ordered the 3" APS dual with our first order, we will see how it does.