I have a 2001 V-6 5 speed that is completely stock. Just have the K&N drop-in filter. I see a lot of folks have added after market mufflers, and others have scrapped the whole exhaust system for a replacement.

I assume most of these replacement systems give a few more hp at the mid to higher rpm range. I'm wondering if that gain is often with a slight loss of power at the low end of the rpm range?
has anyone seen any accurate comparisons of before/ after over the entire rpm range?

I'm interested because I'd go for the change if its not at the expense of low end power/torque. I wouldn't go for it just for the sound.

 

Just from all the posts I've read on the subject, I'd say that a single exhaust is best for low end and duals are better for high end.

Don't know for sure on a V6, but I'd think the same theory applies. I went with the Gibson Swept Side. It's a singe 3" cat back. It's pretty quiet, but has a much better "growl" then the stock one ever had. I'm very satisfied with mine.

 

First I added the superships and was very happy. Then i decided to change the y pipe and muffler in my quest for more. Now i wish i hadnt because i felt that i lost some low end. I put a single in-single out flowmaster deltaflow 50 2.5 inch. Also my tail pipe is now sooty black so i think there might be something wrong with the engine as well. But overall I felt a slight increase in the mid to high range, although i miss the feeling of low end torque and the smoothness of the stock system.

 

I've been really torn on the Y pipe mod myself. You are the second person who has said that they seemed to have lost low end after the Y pipe change.

Mine is still in the box. My thoughts are also that the Flowmasters and other such "Hot Rod" mufflers were originally designed for cars. All the strictly "truck" performance mufflers have all been the round "trash can" style of muffler. That's the way the Gibson is. No scientific facts on this, just an observation.

My muffler guy said I'd lose too much low end if I put that Y pipe in. So I didn't do it.

Just with the 3" Gibson, I'd say I've picked up some low end. Nothing to brag about, but sure didn't lose any. I "know" this because I went to taller tires at the same time I installed the exhaust. I still pull just as hard off the line as with the shorter tires and the stock exhaust. Actually better. Couldn't even really spin the stock setup. I can at least chirp the big tires now with the exhaust.

 

I think on the smaller displacement engines like the V6, opening up the exhaust has a detrimental effect on low end as compared to the 5.4. The reason Ford designed the restriction on the system is to enhance the low end which is neccessary on this heavy trucks with low gearing to save on fuel. Its a compromise because with the stock system, there is no top end on these V6's...mostly noise. Now with my new exhaust, it charges harder on the top end but is somewhat sluggish on the low end. Its a matter of taste really. Its a trade off. Just my .02 cent.

 

I have the V6 also, and installed Gibson's Supertruck exhaust on mine. Got lucky and the dealership I worked for at the time installed it for free. I can not honestly tell you if I gained any torque or hp but it does sound great! I did realize an improvement in mileage (about 2 mpg). Not much, just my 2 cents worth.

 

I put a FM 50 SUV on the stock pipes yesterday. I lost some low end. I am thinking about putting the stock muffler back on.

 

ive got a v6 and i installed a gibson 3inch complete cat back , I did not notice any loss in low end tork it feels like it gained some not alot but some, the guy at gibson said it was to gain about 8 to ten hp and 25 ft pnds of tork that feel to be close.

dale [mr2x75]