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Yet the OP states, "custom bending & flaring was required".
Isn't it just slip fit & a single clamp? Should take all of 10 minutes.
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Isn't it just slip fit & a single clamp? Should take all of 10 minutes.
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I was able to throw together this quick look at our 1.5L fitment installation from last week.
What was your old system?
IMO the Flowmaster FX system looks much nicer with the single Muffler with dual outlets like the stock muffler.
looks are really about last on my list of priorities. ?
I wanted a system where the tip is tucked up out of the way not hanging down. Also I believe the straight thru design of the MRT is going to flow better. Other thing is historically Flowmaster uses the lower quality of stainless steel, 409, which can and probably will develop surface rust. But that’s just my humble opinion. Every one has their preferences. ?
Hey everyone, I was the one that MRT used for the 1.5L last week. MRT did a great job, and have a friendly knowledgeable staff.
as far as the sound and everything. sounds great. no complaints. I would highly recommend MRT
as far as the sound and everything. sounds great. no complaints. I would highly recommend MRT
OP
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I had two Vibrant resonators that Y'd off with dual 3" tips. The system looked good but over time the drone increased to the point it was time for a change. My mileage increased immediately after installing it, now it looks like I might be getting even better with the MRT system. I need a few thousand miles to really tell. I shaved an extra 15 lbs off with the MRT system so that helps a bit also.
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OP
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There really were no issue's, the installation was very straight forward. I should have clarified in my first post about the fitment. I was replacing a custom exhaust that had a slightly different configuration that the OEM. Just enough to warrant new pipe from the factory resonator to the MRT resonator. Super easy install as far as that goes.
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I don't need or want loud when driving around town or out on country back roads. From the review at the beginning of this thread, I'd personally pass on this mod. Even if it proves better MPG or performance, the sound would be a turnoff for me.
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For the sake of science, please do not rely on the indicated mileage on the dash for your fuel economy comparison. Average your fuel consumption over three tanks of gas by hand both before and after. Make sure the driving conditions (city/highway, winds, temps, etc.) are the same both before and after.
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The combined city/highway EPA rating for the 1.5L is 26 mpg. A 20% improvement would put that figure at 31 mpg. If that's the case one wonders why Ford doesn't use the exhaust system you installed.
the reason is NVH… Noise, Vibration and Harshness. Ford wants a very quiet ride with absolutely no drone. Could not believe how quiet my BS was even at wide open throttle.
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I get that. What I don't get is how changing the exhaust system on a turbocharged engine can affect fuel economy. The implication is that a less restrictive exhaust makes the engine more efficient. I don't see how.
The turbocharger is in the exhaust stream. The hot, expanding exhaust gas is what drives the turbine in the turbocharger. This makes the turbine in the turbocharger the primary restriction in the stock exhaust system. Further, the turbine is meant to spin at a given RPM to produce boost pressure to design specification, and the PCM limits the amount of boost the turbocharger makes to protect the engine. That means reducing backpressure, say with a less restrictive exhaust, cannot affect boost pressure without a change to the software.
I can think of no mechanism that would improve engine efficiency by reducing backpressure downstream of the turbine without a change in engine control software.
EDIT: This post is in reference to the specific exhaust system in question. This is advertised as an axle-back exhaust upgrade, which (I believe) replaces the muffler and a few feet of exhaust tubing.
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You're right that the turbo is a major restriction, but what happens after the turbine still matters. If you lower the pressure on the exhaust side of the turbo (by using a less restrictive exhaust), it actually helps the turbo spool more freely. That reduced backpressure creates a better pressure ratio across the turbine, which means the engine doesn’t have to work as hard to push exhaust gases out. Less work = more efficiency.
Even if boost pressure is limited by the PCM, the engine can reach target boost faster and operate more efficiently overall. That can lead to small but real gains in fuel economy, especially during steady-state cruising or moderate acceleration. Plenty of people have seen MPG bumps from exhaust upgrades, and this is why.
It’s not about changing boost levels—it’s about how easily the engine and turbo can breathe.
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