Gear-head exhaust opinions please

[ddvette9]

Waiting to hear from guys like jordo, the mustang guys, etc as you guys seem to be purists and I value your explanations....

To no surprise my (our) top speed is single mid pipe into dual mufflers and the y pipes people are pairing with them, like myself, are wider than stock.

All exhausts worth noting ( berk, hks, FI, Invidia) etc run duals back to a single muffler or dual mufflers like the top speed.

dyne numbers aside, can my gearheads of the world give me a rundown and fellow owners a rundown of air flow, torque effects, backpressure etc. on our VQ and how the VQ reads my intake drop ins with my y pipe and exhaust.

Should be a juicy topic I suspect...thanks

[Methodical4u]

are you getting rid of your exhaust and that's why you're asking?

[ddvette9]

Not planning to. Always wondered

[Methodical4u]

oh, I just thought you were considering another exhaust... I couldn't tell you anything about the rest of the stuff though. I like my set-up A LOT however.

[MattP725]

I don't think your going to get a really dynamic answer as the end user isn't really doing these types of complex analysis on the exhaust and personally I wouldn't trust a manufacturers opinion because they are obviously biased.

From my understanding of the basics, a dual y-pipe is just to equal out the backpressure from each side of the engine. I am honestly not sure why a company would go from a dual into a single midpipe back into a dual, however if your diameter is big enough on the midpipe it probably won't impact performance dramatically (might even increase low end over a dual). I wouldn't worry about air flow or turbulence because the majority of the turbulence would be at the begging of the Y when the gasses meet and equalize.

[370guy]

OK im new to this forum but ive had alot of high horsepower cars and may be able to help.

I just installed the topspeed exhaust you were talking as well and the advantage of the single pipe is the car will have more back pressure thus making more torgque down low. On cars in general, when you make a reduction in back pressure you lose torque downlow. However, on the flipside of that, you gain more horsepower up top with a more free flowing dual.

So the question is, what are your plans for the car? If you ever plan on going forced induction you will need to have a true dual setup because of the increased airflow. With that much more air coming into the motor its going to need to go somewhere. my Previous car (before my Z) was an '09 GT500. that car was running 17lbs of boost so it needed to increased exhaust flow of a big open dual setup (also being a 5.4L V8, it didnt have torque issues haha) but our Z's being a high-reving 6 cylinder in my opinion need the torque. Torque is what you feel, torque is what you need and torque is what makes a car fun to drive. Its what gives you that "kick in the back" when you punch it.

So in my opinion, with a good high-flow car/test pipe, high flow Y and a single you would make ALMOST the same amount of power (equally modded of course) as someone with a dual setup. But again, this is just my 2 cents and im sure some people will think im completely wrong. Just remember, bigger isnt always better. Ill leave you with one last example. my shelby made 532 to the wheels witha full 3in. exhaust. BUT when i put a 2.75 car made 540 and almost 20 ft/lbs of torque more. The right setup is more important

[Methodical4u]

Originally Posted by 370guy

OK im new to this forum but ive had alot of high horsepower cars and may be able to help.

I just installed the topspeed exhaust you were talking as well and the advantage of the single pipe is the car will have more back pressure thus making more torgque down low. On cars in general, when you make a reduction in back pressure you lose torque downlow. However, on the flipside of that, you gain more horsepower up top with a more free flowing dual.

So the question is, what are your plans for the car? If you ever plan on going forced induction you will need to have a true dual setup because of the increased airflow. With that much more air coming into the motor its going to need to go somewhere. my Previous car (before my Z) was an '09 GT500. that car was running 17lbs of boost so it needed to increased exhaust flow of a big open dual setup (also being a 5.4L V8, it didnt have torque issues haha) but our Z's being a high-reving 6 cylinder in my opinion need the torque. Torque is what you feel, torque is what you need and torque is what makes a car fun to drive. Its what gives you that "kick in the back" when you punch it.

So in my opinion, with a good high-flow car/test pipe, high flow Y and a single you would make ALMOST the same amount of power (equally modded of course) as someone with a dual setup. But again, this is just my 2 cents and im sure some people will think im completely wrong. Just remember, bigger isnt always better. Ill leave you with one last example. my shelby made 532 to the wheels witha full 3in. exhaust. BUT when i put a 2.75 car made 540 and almost 20 ft/lbs of torque more. The right setup is more important

I have actually read that an FI'd car is better off with a single pipe... this is supposedly of course.

[ddvette9]

So the Top Speed creates more back pressure than the other exhausts for our car meaning more low end torque vs a traditional cat back but less top end HP......this is the information I was looking for

[370guy]

I havent dyno'd it yet (just installed yesterday) but thats what general exhasut info would say. More back pressure means more low end torque. duals would yield higher horsepower numbers, but in the top of the RPM band. so what ou have to ask yourself is, where does your engine spend most of its time? mine definitely spends 95% of its life below 6K haha (unless of course its at the track).

@methodical4u I wouldnt be surprised at all if these cars made more power on a single pipe setup. It would make sense. Thats why i went with Topspeed