I am thinking of gettting the flowmast single in dual out the sides exhaust system for my 2003 5.4 liter v8. My only concern is am i going to have to give it more gas then i have to now cause my tourque and hp will be up in the rpm range alittle bit more. How have you all that have a dual exhaust/pipes out of a single pipe been affected.

 

I have true duals with glass-packs, which is pretty unrestrictive, and I noticed a little loss in low end due to the loss in backpressure. It wasnt really noticable, and the little that I did loose, is made up for by the sound

From what I have read though, the Flowmaster systems are actually MORE restictive than stock-to restrictive in fact, and thats causing some low end loss for some.

You might want to consider something other than Flowmaster. Magnaflow has nice systems, and they actually GAIN you power down low, instead of destroy it.

 

I have the Flowmaster 50 with SI/DO. Sounds good. I haven't noticed any low end torque loss. Check photo in gallery.

 

05 Screw 5.4 I have the Flowmaster DIDO exhaust. I did notice a slight loss of torque in the 1500 rpm range but the sound more than makes up for it. I am more than happy with my Flowmaster.

 

The said "loss" of torque or horsepower is so minimal its not worth even mentioning. Your talking about a numer between 2 and 4. one a 200hp vehicle, 2 is 1%, 4 is 2%. you won't even be able to tell the difference, and if you further modify your vehicle that loss is, in my opinion, negated. And it sounds badder than hell so you can't go wrong

 

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