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3K views 16 replies 11 participants last post by  bringler26 
#1 ·
Ok, curious

I consider myself a "car guy" but certainly no engineer.

Given that I dislike the 4cyl sound, I refuse to get a "fart can" muffler for my car. I'd prefer that she's as silent as possible, but don't want to sacrifice the gains of a free-flowing exhaust.

My question is this: Dual exhaust? If I want silent mufflers, would adding dual exhaust (after the cat) negate the backpressure from the type of muffler/resonator that I'm looking for?

I've done some research on the subject here, and the general concensus seems to be that dual exhaust is pointless aside from looks, but no one has broached the subject of a restrictive muffler design as part of the concept.

Thoughts?

[confused]
 
#5 ·
I have a 2.5" Borla with zero rice sound. It grumbles when rpms slow down, it's awesome. In the morning when it's colder, it drones a bit and annoys my neighbors so I may go with an added muffler, which would basically be the same layout then as the FSWerks stealth.
 
#11 ·
Having a 'dual exhaust' on a 4 cylinder won't really net you a quieter exhaust. Exhaust will always favor the shortest route. Yeah, a little exhaust will go the longer route, but your shortest path is going to get the most exhaust through it.

You can get the FS Stealth exhaust, but you could always buy a resonated exhaust with whatever muffler & that will be about the same & may or may not be cheaper depending on your connections. I'd recommend going the stainless steel route with whatever you choose. Its going to last longer than aluminized steel, which will rust out much quicker than stainless.
 
#13 ·
Usually the scavenging effects on the 4 cyl are needed if you split it right after the CAT you could potentially lose some performance (that's why H pipes or X pipes are usually an addition to the dual exhaust on the V8's.

You could do something at the rear of the car if room using a single inlet dual outlet muffler. I always think its weird in the winter though when you see 90% of the "steam"/exhaust fumes coming out of one tail pipe and nothing out of the other. the whole will flow the path of least resistance.

the FSworks stealth exhaust is one of the best. you could go with a 3" from Trubendz and then add in a large and long resonsantor but would most likely be more costly than the FSworks Stealth exhaust.
 
#14 ·
Amen brother. Dual exhausts cost power on 4 cylinders, you need the flow down a proper sized pipe to scavenge head better. Generally more noise, hey you bought the four, ALL fours have potential to make more noise, the exhaust pulses are far enough away from each other they do not interfere with each other to kill noise. Look how single exhaust on a V-8 kills noise compared to duals, the cramming in there of all those sound waves kills power but kills noise too.

You can forget any ideas of necessary back pressure as old wives tales that cost you power. You want pressure as low as possible.
 
#16 ·
I believe you will be fine as along as you don't go with a straight pipe, some cheap muffler or upgrade nothing but the muffler.
 
#17 ·
Single exit is your best bet. I have heard the Borla and it sounds deep and not raspy. Most well put together Focus exhausts don't get the cheapo sound that the Civics tend to have(due in part to some of their owner's having cheap tastes).
 
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