I've been reading through the forum for the past few days and it seems like everybody has their own opinion for which exhaust systems is "the best". As for myself I have a 99 F-150 4.6L and I am looking for a system that has the performance gains without the torque loss. I have pretty much decided on a SI/SO-3" exhaust. I also don't want to be waking up the neighbors, but I do want to know that it is there. From what I have read and researched online, that will lead me to either a Gibson, Dynomax Super Turbo, or the Magnaflow. Does anyone know which will "out perform" another? Which is the right sound? Form what I have gathered the Dynomax Superflow has much less flow than the Dynomax Ultraflow. This is my first post so I don't know what to expect. I have recently purchased the K& N Gen II, if that makes any difference.

Thanks Naylordog

 

I am pretty much thinking about the same thing right now I had my truck close to 2and a half years and still have the stupid stock exhaust system on it I'm thinking of going with Flowmaster but would like some opinions on the gibson and other aftermarket exhuast systems before I go and get one.

 

I did more research and one guy recommended the flowmaster 40 series and said that would be the right sound I am looking for. I am going to go on Saturday and have a listen, so I can let you know then. I got a chance to hear a Dynomax Super today and those are really quiet!! So I guess that is off my list.

 

Naylordog,
I have the Dynomax Ultra Flow exhaust and I highly recommend it. It has a very good rumble at start-up and during acceleration but is hardly noticeable in the cab while driving on the highway. I also noticed a better throttle response after installing the system.
FYI Mine is a SI/DO muffler on a 5.4L engine.

 

The Flowmaster "regular" 40 does sound nice, although it is not stainless steel nor does it flow well (under 400cfms). The Super Turbo is mellow and has similar flow. The Ultra-flow has a throaty muscle car sound. I'm very pleased with my tone and get compliments and looks all the time. I've had many mufflers on many cars and none sound better or have higher flow rates (which is crucial on a single muffler application).

 

Thanks for all the info...I have decided that I am going to go the new muffler and keep the stock exhaust system. My only decision now is between the Dynomax Ultraflow of the Flowmaster DeltaFlow series and if so the 40 or 50. I need to hear these to make up my mind. I have been reading that the Ultraflow system has much better performance but that's what the website says...who knows what testing they have done. Which of these will have the least interior resonance?

 

If you want much sound out with the multi-cat setup, get a loud muffler. The DF 50 is not loud, the DF 40 is moderate, the Regular 40 sounds throaty. If I was using my factory stainless steel pipe, I'd get a stainless steel muffler to replace my factory muffler; just an opinion. The Flowmaster has a low flow rate, will rot inside out in no time being mild steel, and is commonly complained about here losing low end torque. Much better mufflers are available: Ultra-flows, Magnaflows, Borla, Edelbrock, etc..all in stainless steel. Tell us how things turn out.

 

This is what I decided to do after hours of research. I went with the Flowmaster 40 original series muffler and left the stock pipes on it. I had the shop put a 3" diameter 8" tip on the end. I too did not want the loud sound and amazingly this is the right sound I wanted. Not loud by any means and there is almost no in cab res. This is due to the fact that the muffler location is back under the bed. I originaly thought I wanted the 40 of 50 Delta Flow but after listening to the set ups that would have been too soft. Currently I will not wake anyone up with this muffler. I have noticed better gas milage and also no loss on low end torque a definate gain in top end torque. The guy at the shop recommended the 40 original because if you just swap out the muffler the Ford's run 4 cat's and that is overkill as it is. Anyway, I am really happy so far.

 

The flowmaster 50 series on my '83 cost $139 and thats a cat back system.The last one I paid for was in 2000.Also have had bad juju's with Flowmasters splitting after the warranty ran out.

I paid $200 for the Magnaflow 3' catback on my '01 S_crew.

The Magnaflow costs alittle more but they have a better warranty and I noticed a greater torque increase with the Magnaflow.
They installed both the 70 series Flowmaster and the comparable Magnaflow on my baby to let me see the difference.
I think the Magnaflow sounds better too.

 

Sorry if this is a stupid question, but where are you guys buying these mufflers and approx what is the cost.

my wife is not "Loud" mod friendly but I would like to install a new muffler with all the stock pipes intact and not too loud I want better performance over sound

thanks

 

Where can I get the Magnaflow Cat back for $200 ?

 

naylordog

How did you decide on the 3" tip? Does the tip enhance the overall sound that much? I also have a 1999 with a 4.6 and am considering the same setup.

 

The tip is really for looks, I didn't want to have a tail pipe sticking and I also didn't want to have a 2 1/2" tip either. They just fitted the tip (3") on the stock exhaust pipe (2 1/2") and that was all there was to it.

 

my super turbo kit si/do will be here bythe end of the week i will post any results