I'm installing the APS TT in a few days and will be making a custom true dual exhaust. I already have the APS 2.5" test pipes.

I know 3" exhaust will be super loud and I dont want to deal with that. I was thinking either 2.5" or 2.75" just like the Greddy EVO TT exhaust. bear in mind that I plan to build the motor down the road and reach 550+ whp. what size piping should I go with?

anybody have pics of a custom TD exhaust?

 

Dubai, good luck with you new setup.

 

If you have only 2.5" test pipes you aren't going to see much difference, if any, with a larger exhaust after the testpipes. Might as well go with the 2.5" if your goal is to keep it quiet. Did you perhaps mean APS 3.5" testpipes?

If you are going to build a motor down the road and you think you might go with larger downpipes/testpipes later, it wouldn't hurt to go with the larger size for future upgradeability.

 

if you want 550hp you're going to have to deal with it cuz it will be loud

 

Thanks for the inputs. the APS TP's I have are 2.5"

so what I understand is that I have to run testpipes bigger or at least same size piping as the exhaust? if the testpipes are smaller than the exhaust that wouldnt make much difference? can someone confirm this?

 

The test pipes will be your bottlneck right now but I would personally go with the SVR tech 3" Dual

 

Love my EVO TT

 

what test pipes are you running? is it loud?

 

I would sell the 2.5" pipes and get a set of the 3.5" dump pipes and pair it with the 2.5" APS exhaust. the 2.5" will flow enough for 550+ whp. You will just need to make sure you have strong actuators on your turbos. The evoTT from greddy looks nice, but still bottle knecks to less than 2.5" where it bolts up to the dump pipes.

 

If you hold off for a few days i will be try something new. Right now i have 3 inch and it is a little loud but the flow is awesome. There is a new muffler from dynomax i beleive that has two 3inch in and 2 3inch out. That with some highflow cats should quiet it down. Hopefully i can get it done today. And i can let you know. I have heard it on a few turbo cars and it did quiet it down alot. But this will be the first z we test out.






UPDATE.

Dude, I tried something else and it turned out awesome. It is no longer noisy. This is what i did. We ran off the 3.5 inch extreme downpipes 3 inch exhaust into two 3inch Magnaflow highflow cats. Then we ran 2 3inch highflow mufflers and it sounds sweeet. I will try and post some video sound clips for you guys.

 

I currently have this muffler with two metal cats:

"There is a new muffler from dynomax i beleive that has two 3inch in and 2 3inch out. That with some highflow cats should quiet it down"

Mine is not "too" loud but it drones badly at 2500-3k rpm.

Does your "updated" setup drone at all?
Which mufflers used?

 

my dyno


I love the APS 2.5 Exhaust, I have the 2.5 APS test pipes but will go with the 3 test pipes and stick with the 2.5 exhaust. According to APS that will let me gain another 80 whp but won't be as loud.

 

I didn't realize you were still running the 2.5" test pipes. I think 80 whp is a bit optimistic, but I definitely think they will help considerably. hell, how much more power do you want anyways?

 

Maybe it is just me, but having HFC would defeat the purpose of having the 3" exhaust. At that point, stick with the 2.5" with test pipes which in my guess would outflow a 3" paired with 2 cats

 

hell at this point I just want a car doesn't break every time I take it to the track and is then down for weeks...

 

It doesn't hurt the flow at all. We also but on the same setup a greedy evo #2 and it hurt about 31hp. The 3inch high flow cats are bads ***. The car really doesn't drone. But i did notice a little rattle at low rpm's. When we put it on the lift we saw a bracket rubbing.

At 8.8 psi it is making 440rwhp 5at I think the airflow is fine.