350 Vortec Sluggish...Why?

[Guardian]

It has to do with the scanvaging effect on the cylinders. The 2 2" feeding into one 3" acts like a vacuum chamber on the exhaust system because it lowers the pressure , then the split to 2 2" again will increase the exit velocities and allow for better scavaging.

 

[DoubleDingo]

It has to do with the scanvaging effect on the cylinders. The 2 2" feeding into one 3" acts like a vacuum chamber on the exhaust system because it lowers the pressure , then the split to 2 2" again will increase the exit velocities and allow for better scavaging.

Soon I will be swapping out the single exhaust on my '81. I have a Borla dual in/dual out muffler. So the way you describe it, I should run (2) 2 inch pipes into a 3 inch pipe and then since the muffler is a dual in/dual out it should act as an "H" pipe for the duals going out the back?

 

[GOBR]

The new Chevy/GM trucks have a 3" inlet with a 2.5" outlet. I have a Magnaflow 1 in 2 out in the garage right now that came off a new Chevy. The smaller the number the more tq the higher the less. 2.25 is sufficient with a mild engine. A 1 in 2 out Magnaflow or a "knock off" Magnaflow is your best bet. It will sound good and open up when you romp on it and it will have the power. I have 2 3 chamber flows, true duals and they are quiet but when you get down on it they open up big time. Im bout to swap to an X pipe with dynomax bullets....... Oh yes son!

My exhaust is 2.5 true dual with longtubes turned down at the axle.

 

[Jims86]

So what goes into the single 3in? 2 in pipes off the manifolds or collectors to 3in muffler, then split coming out to two 2 in again? So do you use a 3in inlet with dual outlets? Esplain it !!!

I had 2.25 pipes from each manifold, 2 cats into a dual 2.25 in/single 3" out muffler(where a y pipe would normally be) to a longer case, single 3" in/dual2" out....cind like a long ass rocket tail spout.
In the beginning, I did have the flowmaster Y where the first muffler was after the cats....I wanted the extra muffler as a resonator.

 

[HotRodPC]

I'm being told, some places to go off-roading in a 4x4 truck, they require resonators or spark arresters to prevent fires. WTF??? For real? I can understand on ATV's or 2 stroke dirt bikes but trucks too???

 

[Guardian]

Soon I will be swapping out the single exhaust on my '81. I have a Borla dual in/dual out muffler. So the way you describe it, I should run (2) 2 inch pipes into a 3 inch pipe and then since the muffler is a dual in/dual out it should act as an "H" pipe for the duals going out the back?

IT will help with the torque band and will smooth out hte exhaust pulses for a smoother performance and sound.

 

[DoubleDingo]

IT will help with the torque band and will smooth out hte exhaust pulses for a smoother performance and sound.

Sounds like I have minimal modification do get this set up on my truck. Just need 2 feet of little large diameter pipe, a y-pipe, and about 10 feet feet of 2 inch pipe out the back.

 

[Jims86]

Sounds like I have minimal modification do get this set up on my truck. Just need 2 feet of little large diameter pipe, a y-pipe, and about 10 feet feet of 2 inch pipe out the back.

Shane...where in cali are you?

 

[HotRodPC]

Did we lose Shane?

 

[DoubleDingo]

Did we lose Shane?

Shane left the building...lol...Shane come back...come back Shane...lol...