Couple of questions... Is there any benefit with going with a Single-in/Dual-out muffler verses going with a Single-in/Single out? I'm mostly interested in gaining a little bit for towing, and of course a good sounding exhaust. I really don't care for the dual-out-the back setup, and the dual same-side exits that I've seen require that the spare tire be removed. I also like the exhaust that exits in front of the tire, but the only setup that I've seen for a 1999 4.6L is the Gibson Super Truck, which I fear will be too loud for me, and may not be the best for towing.. I had thought about just replacing the stock muffler with a high-flow SI/SO, and keeping the rest stock. Would I really gain much with this, or would I really need to go with a complete cat-back system?

Thanks,
Joey

 

The single in single out is going to have more low end power more than likely. You could do a 3" SI/SO for optimum performance. 2.25" tailpipes for a dual application would probably be close to the same, but maybe just a hair less low end.

Catbacks are a waste of money. Go custom. Check into Borla Pro XS mufflers for awesome tone and great low end.

 

I'm really interested in the Aero Turbine exhaust. I heard it on another 4.6L and it sounded great. Plus it's 100% stainless steel. Anyway, the have a SI/SO muffler that is 2.5 in / 2.5 out, as well as one that's 3.0 in / 3.0 out. Would it be better to go with the 2.5 in/out vs the 3.0 in/out for low end power? They also have one that's 2.5 in, and 4.0 out...

Any added benefit to also replacing the exhaust pipe from the muffler back?

Thanks,
Joey

 

I also am a fan of the Pro XS mufflers!

 

How are the Borla Pro XS mufflers at cruising speed? I want a good sound, but nothing loud at cruising.

 

Magnaflow and Borla make stainless steel cat-backs for '97+ Ford trucks.

And these trucks can clear 2.5" tailpipes with no issues with the spare tire.

Anyways the SI/SO wont be as loud as the SI/DO but they will perform the same. Some have quoted the SI/SO to be the best for towing for full velocity.

 

Its not bad at all at cruising speeds. I have high flow cats and 14" true duals and its not bad at all.

 

do not exceed the 2.5" diameter. YOU will lose your low end torque. I put a SI/SO on my old 4.6 and regretted it for the low end loss. I do felt like she moved better in the upper RPMs though. But for around town it sucked.

 

THanks for the info. Sounds like I definitely need to go with a SI/SO in 2.5 inch diameter. I definitely don't want to lose any low-end torque.

 

Borla Pro XS!

 

i was wondering the same thing and a custom car shop told me you can get more power from SI/SO do to less bends in the piping. i just installed a banks monster exhaust today and love it. with the cold air intake it sounds great and almost as quiet at stock cruising. It has a very deep tone.

 

Same here...

 

Any chance that I may actually loose low-end torque by adding a higher-flow muffler? I'm planning on sticking with a SI/SO, and most likely same pipe diameter. I definitely would like a better sound that an aftermarket muffler will provide, but I don't want to hurt my low-end torque. I actually would love to improve it.

 

Here's something else that I've been thinking about. I love how the exhaust looks when it exits in front of the tire. How would using a 2.5" SI/SO muffler wth pipe customized to exit in front of the tire impact the performance? Definitely alot less bends in the exhaust pipe than what it would be using the stock pipe exiting behind the tire.. And I found a sweet exhaust tip on ebay that is a SI/DO and is angle / slant cut. Definitely the look that I'm going for, but just want to find out how it will impact my performance...

Thanks again,
Joey

 

It will run fine, no torque loss, that goes for your above post about adding the higher flowing muffler too. It will improve.