exhaust with best low end...
on my 4.7 i did gibson headers and left the crossover pipe cause stock is 2 1/4 and mine had high flow cats from the factory and i unbolted the muffler and tailpipe and got a 2 1/4 to 2 1/2 adapter welded to a single 2 1/2 in with dual 2 1/2 out with turn downs in front of the rear end and it hits the exaust hanger and keeps my low end torque and gives it a nice mellow sound to it at idle and a nice rumble to it while driving
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Champion
Joined: Jun 2008
Posts: 3,300
Likes: 2
From: Plattsburgh, NY
Loud 3.9 = fail
Registered User
Joined: Nov 2009
Posts: 7
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i was running a straight y-pipe in front of the tires on my last truck, a 4 cylinder, and had a difficult time getting it inspected... this one i want to be inspectable, im running it in front of the tires, but with mufflers and all... i want it as loud as i can that way, but i dont want to sacrifice any power or anything....
Hall Of Fame
Joined: Jun 2005
Posts: 14,228
Likes: 19
From: Riverton, UT
The correct way is a tuned exhaust. Most people tend to over due it or under do it. The correct way for doing a system is to first look at OEM.
I seen some miss conceptions....IMHO....in this thread. The first thing is you NEED some back pressure but also velocity and flow design what I like to call a tune of "Balanced Flow Design".
Now we are NOT running +6000 RPM's here so the mid and lower end of the power band is what you want. To do this you need to look into the OEM design. Sure everyone looks at this and is going to laugh but let me first start telling you this, How many MILLIONS of $$$$ and how many engineers were needed to build a motor and exhaust and who is 1 or 1000 people to tell them that they were incorrect?????? I call BS!
I know of people that put full systems on their vehicles not to gain even 1 HP or Torque so the idea of getting a nice velocity flowing design isn't the best idea. Now I'm not saying they didn't get a better power curvature but the bottom numbers didn't move! The issues here were that the exhaust was tuned "Balanced Flow Design" from the factory.
Now we get someone who simply said I CAN MAKE IT BETTER......LMAO......Ya right!
Well in less you have experimented in dropping exhaust in Hi rpm motors, yes a nice dump is necessary but in low to mid rpm motors it takes up to much room to fill the pipes therefore a loss in torque. Now I have personally completed different designs in engine building and exhaust flow and have found that installing long headers resulted in lose of torque in the low end. Now on the hi end, I gained but I'm talking 5000 to 6500 rpm areas. Now I don't know about you but I tend to run in the 1000 to 4500 area and not the hi end so if I'm adding headers or a larger exhaust then intake work is needed to off set the "flow design".
This brings me back to the OEM versions. Now the OEM has about 3 lbs back pressure. This is too much....IMHO....and I like the 1.5 to 2.5 range for the RPM's that I run. This range gives you the low end grunty pulling torque that we all like and the mid range rpm that I run in. This is better for around town driving and pulling the hills as well as towing. I have 2.5 lbs back pressure and can tow like mad, I have great low end torque, mid range power but it drops off at about 4000 rpm's. I have a 3" CAT back MagnaFlow system.
My system also incorporates a Ram Air CIA, Ported and Polished heads, bored 30 over 5.9L, and custom intake manifold, and MSD ignition. With this set up I plan on going to shorty headers, new 2.5 inch down pipes to a 2.5 X 2.5 X 3 inch "Y" pipe into a Hi Flow 3 inch CAT. All this connected to my CAT back system I currently have installed. To aid in stuffing this exhaust I plan on going to 1.7:1 lift rockers, M1 intake manifold, and a different flash. Depending on how that runs I will get into it further. Then main idea I am describing is a tune exhaust system to the motor/driver/RPM and not some overall idea of what someone says is better.
Just throwing headers and an exhaust on is going to give you a newly refined running machine but you are going to loose torque! You are going to gain in other ares like Hi range but what I'm saying is "don't expect some outlandish increases just for bolting on a few pieces". You have to do more work than that!
If you are a newbee in this let me tell you this.....IMHO..... If you want a better system with fuel mileage and approximate better values then stay close to OEM. Start with a little bigger piping from the Catalytic Converter back and add a different intake design like a Hi Flow K&N drop in filter and a true Cold Air Intake (CIA) from the outside and not one of these systems you find on Ebay. The muffler should be a Hi Flow design of your choice (I like MagnaFlow) to each their own. If you want a little more power and gas mileage then just install a K&N drop in filter and replace the OEM muffler and go with a direct replacement Hi Flow design like MagnaFlow or Flowmaster or other.
I seen some miss conceptions....IMHO....in this thread. The first thing is you NEED some back pressure but also velocity and flow design what I like to call a tune of "Balanced Flow Design".
Now we are NOT running +6000 RPM's here so the mid and lower end of the power band is what you want. To do this you need to look into the OEM design. Sure everyone looks at this and is going to laugh but let me first start telling you this, How many MILLIONS of $$$$ and how many engineers were needed to build a motor and exhaust and who is 1 or 1000 people to tell them that they were incorrect?????? I call BS!
I know of people that put full systems on their vehicles not to gain even 1 HP or Torque so the idea of getting a nice velocity flowing design isn't the best idea. Now I'm not saying they didn't get a better power curvature but the bottom numbers didn't move! The issues here were that the exhaust was tuned "Balanced Flow Design" from the factory.
Now we get someone who simply said I CAN MAKE IT BETTER......LMAO......Ya right!
Well in less you have experimented in dropping exhaust in Hi rpm motors, yes a nice dump is necessary but in low to mid rpm motors it takes up to much room to fill the pipes therefore a loss in torque. Now I have personally completed different designs in engine building and exhaust flow and have found that installing long headers resulted in lose of torque in the low end. Now on the hi end, I gained but I'm talking 5000 to 6500 rpm areas. Now I don't know about you but I tend to run in the 1000 to 4500 area and not the hi end so if I'm adding headers or a larger exhaust then intake work is needed to off set the "flow design".
This brings me back to the OEM versions. Now the OEM has about 3 lbs back pressure. This is too much....IMHO....and I like the 1.5 to 2.5 range for the RPM's that I run. This range gives you the low end grunty pulling torque that we all like and the mid range rpm that I run in. This is better for around town driving and pulling the hills as well as towing. I have 2.5 lbs back pressure and can tow like mad, I have great low end torque, mid range power but it drops off at about 4000 rpm's. I have a 3" CAT back MagnaFlow system.
My system also incorporates a Ram Air CIA, Ported and Polished heads, bored 30 over 5.9L, and custom intake manifold, and MSD ignition. With this set up I plan on going to shorty headers, new 2.5 inch down pipes to a 2.5 X 2.5 X 3 inch "Y" pipe into a Hi Flow 3 inch CAT. All this connected to my CAT back system I currently have installed. To aid in stuffing this exhaust I plan on going to 1.7:1 lift rockers, M1 intake manifold, and a different flash. Depending on how that runs I will get into it further. Then main idea I am describing is a tune exhaust system to the motor/driver/RPM and not some overall idea of what someone says is better.
Just throwing headers and an exhaust on is going to give you a newly refined running machine but you are going to loose torque! You are going to gain in other ares like Hi range but what I'm saying is "don't expect some outlandish increases just for bolting on a few pieces". You have to do more work than that!
If you are a newbee in this let me tell you this.....IMHO..... If you want a better system with fuel mileage and approximate better values then stay close to OEM. Start with a little bigger piping from the Catalytic Converter back and add a different intake design like a Hi Flow K&N drop in filter and a true Cold Air Intake (CIA) from the outside and not one of these systems you find on Ebay. The muffler should be a Hi Flow design of your choice (I like MagnaFlow) to each their own. If you want a little more power and gas mileage then just install a K&N drop in filter and replace the OEM muffler and go with a direct replacement Hi Flow design like MagnaFlow or Flowmaster or other.