well I finally got my exhaust put in yesterday(Full 3" Y-pipe back, 14" magnaflow) and today on my way to work I notice that my truck was over 2K a lot more than with the stock exhaust...and it feels a BIT sluggish at take off(feels way better up top though!) but did I loose a lil torque because of the larger pipe size????

thanks in advanced

07 fx4 5.4 BTW...

 

man it seems like a very good exhaust set up. i dont see why you would be losing any low end. 3" to a si/do set up is kind of ideal imo. i had the exact same set up at one time but with a flowmaster and i loved it, no loss of low end at all. Darren might know whats up.

 

07FX4, I don't no why you say that? I have a 3" in dual 2.5" with high flow cats & super 44 and I always bark my tires, I have lots of low end power. I heard of people lost low end torque with true dual exhuast. Do you have a custom tune? May be custom tune will help you out.

 

if the only modifications were from the cats back I cant see it...maybe if you put in a slowmaser but not a magnaflow.

 

Here we go again! Give it a brake already! If you Like crapy sound then good for you.

 

Again? first time ive spoke badly about flowmaster...but sorry to say its dyno proven.

 

u girls are annoying

07FX4: what kind of piping did you use? mandrel bent, smooth bent, or crimp bent? crimp could be why you lost some torque, thats really bad flow with the crimps.

 

who would dyno a 4x4 truck lmao
ya'll know these aint drag trucks running a keith black hemi ...right

 

There is so little power difference in a stock truck between flowmaster and magnaflow. I love how everybody makes it sound like you gain 50hp with one muffler brand and another brand loses 50 hp, lol . I've had both on my truck and the flowmaster is a mans muffler, the maggie well you get where I'm going!! Both brands have stainless steel options now also.
Mufflers on a stock truck are for sound, you aint going to get anything else out of it that is even worth mentioning
Both mufflers I had on mine brought lower mpg numbers for me, and the flowmaster felt better low end and crappier high end, the magnaflow felt like I lost low end, but better high end. It wasnt any kind of a big difference then stock except the sound. I'm back to my stocker now and I've gained a very good % of gas mileage back and other then the truck being really quiet theres no difference in performance that you can even notice while driving it. So give it up already and stick to the guys topic.

07 fx4, what type of bending did they use? Post some pics of your set-up. The way it sounds as you drive also sometimes plays a role in what you think of it too because if it sounds like it struggling it may make you think you lost power, but its just the sound, and not struggling at all.. you see what I'm saying?

 

I would like to read a post with out any one saying Flowmaster muffler sucks. This form was about losing torque, not mufflers but you see the Magnaflow people can't keep there mouths shut. I have never put down Magnaflow intill this tread pist me off, I use high flow cats from them but I'm just tired of every post I read some one has to put down Flowmaster. Migdaddy that's not real nice to say.

 

Interesting you should say that because I gained low end as well as top and I also gained gas mileage. If you look at the physics behind it you'd realise that you could only gain mileage and power (if its not more restrictive than the stock). The reason you lost mpgs is probably because you are harder on the throttle and accelerating at different rpms than you would with the stock exhaust.

 

Are you serious?

 

on my superduty 5.4 van it came stock with 3" siso exhaust, going from that to a mandrell bent 2.25" x-piped dual exhaust with magnaflow mufflers, my bottom end increased tremendously, i tow
~5,500 lbs every weekend, compared to my other 7 - 5.4 vans that still have te 3" oem exhaust on, they can't hold a candle to this exhaust...

 

It is probably because of the Y pipe area, is it 3" from the Y pipe? or the OEM Y pipe cut out and 3" fabbed from there?

 

Well it doesnt matter about physics cause all I know is the numbers were 2-4mpg worse with cat-back compared to stock. And driving style is identical, actually I probably hammer on it more without the cat-back because I cant hear the damn truck any more, lol!!

good thoughts, just not right results, sorry