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Discussion Starter · #1 ·
Anyone know what the weight of the factory muffler is as compared to performance mufflers. I know when I replaced the factory muffler on my 97 Saturn, with a budget Magnaflow performance muffler, I save at least 25 pounds, which I attributed to my 2-3 mpg improvement. I am hoping for some weight savings with the Cruze, and maybe a bit of an MPG improvement.
 

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I think what they're saying is that it is highly unlikely that removing 25 lbs attributes to 2-3 mpg in a Cruze. Two male passengers who weigh 200 lbs each may cause a reduction of 1 mpg (based on -1% mpg per 100 lbs rule of thumb).
 

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Discussion Starter · #5 ·
Thank you Steelmesh. Your rule of thumb info is exactly what I was looking for; that even the slightest weight reduction can make some improvement seen mathematically, so though it may take 5 years for a new performance muffler to pay for itself, at least there will be some savings....
 

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Thank you Steelmesh. Your rule of thumb info is exactly what I was looking for; that even the slightest weight reduction can make some improvement seen mathematically, so though it may take 5 years for a new performance muffler to pay for itself, at least there will be some savings....
Yes, weight makes a difference for sure and it can add up, eventually. If you save 25lbs, rule of thumb does suggest a 0.25% improvement to gas mileage, but the error in the rule could be +/- 0.25%, so that puts you into near 0 mpg improvement as a possibility.

Just thinking, if I was passionate about improving mpg and wanted to keep my LT, I would start researching all of the Aero mods GM added to the Eco trim, then start adding these modifications based on price vs. performance.

Without regards to engine calibration, here are the factors effecting MPG performance (taken from lecture on sizing hybrid systems in cars):

F-tractive = the force needed to propel the vehicle

F-tractive = F-accel + F-rolling + F-drag + F-hillclimb

F-accel, not needed for mpg cruising but included to meet acceleration performance needs of the vehicle, F=ma

F-rolling = (Rolling Resistance coefficient)*mass*gravity

F-drag = 0.5*(air density constant)*(Coefficient of Drag)*(Car Frontal Area)*(Velocity)^2

F-hillclimb = (mass)*(gravity)*Sin(slope angle)

The goal is to make changes to the elements in these formulas to help improve gas mileage by reducing the Force required by the engine to maintain a speed. The problem is identifying what will make the largest impacts. In very hilly or mountainous regions, I can tell just by looking at these formulas that weight reduction will have more impact than flat regions, but I am not concluding how big of an impact it is.

What sticks out for me is the Velocity^2, which means the faster you go there is a biased increase in the force required to maintain that speed, the force required is "exponential". So if you really want to go 70 mph, then you need to reduce the elements that multiply into the Velocity part of the formula because those elements are amplified by the exponent. You can move into the mountains to decrease air density (or move to a super ultra humid place click for source), improve the coefficient of drag (Eco mods), reduce the frontal area of the car (lowering), don't drive as fast duh :p Then for F-rolling, air up your tires more than factory spec to reduce the rolling resistance.
 

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Discussion Starter · #7 ·
Today I had American Muffler, Brake & Radiator; here in Thousand Oaks, install a new Magnaflow polished stainless steel Universal Performance muffler (Part No. 14210) on the Cruze. It is 17" total length, 5"x8" oval body, with 3" long 2.5 dia necks, and about 10 pounds lighter. USA MADE! They were able to use the factory hanger, and simply added some tapered tubing between the factory tubing and the necks on the muffler. Surprisingly, it is not any louder than the factory muffler.

Additionally, today I tanked up on 91 octane, so I will evaluate if the higher octane pays for itself in combination with the new muffler. Excited to see...
 

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Today I had American Muffler, Brake & Radiator; here in Thousand Oaks, install a new Magnaflow polished stainless steel Universal Performance muffler (Part No. 14210) on the Cruze. It is 17" total length, 5"x8" oval body, with 3" long 2.5 dia necks, and about 10 pounds lighter. USA MADE! They were able to use the factory hanger, and simply added some tapered tubing between the factory tubing and the necks on the muffler. Surprisingly, it is not any louder than the factory muffler.

Additionally, today I tanked up on 91 octane, so I will evaluate if the higher octane pays for itself in combination with the new muffler. Excited to see...
Congrats on the install, You like the sound of it?

As for 91/93, make sure you have KRD on the "DO NOT REMOVE" sticker in the glove box. Also if this is your 1st time, don't expect it to be stellar. You need to run at least 3 tanks to flush the 87 and make the computer trust you. it will give you 91 fuel map when you fill up but switches to 87 map after 2 pulls no mater what fuel you used in the 1st 2 tanks.

Also take into account if you live where winter temps are wild. Here in the rust belt I can have 20F temps and 68F temps in 1 tank of "Winterized Gas" gas so remember longer warmups and excessive idle can take away MPG.
 

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Today I had American Muffler, Brake & Radiator; here in Thousand Oaks, install a new Magnaflow polished stainless steel Universal Performance muffler (Part No. 14210) on the Cruze. It is 17" total length, 5"x8" oval body, with 3" long 2.5 dia necks, and about 10 pounds lighter. USA MADE! They were able to use the factory hanger, and simply added some tapered tubing between the factory tubing and the necks on the muffler. Surprisingly, it is not any louder than the factory muffler.

Additionally, today I tanked up on 91 octane, so I will evaluate if the higher octane pays for itself in combination with the new muffler. Excited to see...
Did you replace the resonator in the mid pipe and leave the factory muffler on? Also in 11-12 the 1.4 and 1.8 had the same super huge resonator on the mid pipe where in 13 and up they shrink it to 1/4 the size of that for the 1.4 and left the 1.8 huge. Did you have video of it?
 

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What I want to know is what is officially considered the resonator and the muffler on these cars?

Is the unit on the mid pipe running down the length of the car the muffler and unit horizontal at the rear the resonator?
 

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Thank you very much. I just wanted to understand, because that is against logic it seems, normally a resonator is after the muffler. I want to get a muffler to add some rumble on the outside and in general, but not take away from the quiet inside as I commute 100 miles a day, drone really is the killer, not more sound. I come from the v8 truck world, so I have learned how to have a loud, deep, great sounding exhaust, and keep drone to a min.

So a nice 18"-22" magnaflow muffler would great and not increase drown really.
 

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Part of my long reply was the size difference between the 1.4 resonators before and after 2013 model year. I'm not buying that GM managed to make the smaller resonator sound the same as the larger one so muffler deletes can't be the exact same sound for all years 1.4T. That being said, the muffler delete is around the same db as Abarth 500 stock range.
 

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Part of my long reply was the size difference between the 1.4 resonators before and after 2013 model year. I'm not buying that GM managed to make the smaller resonator sound the same as the larger one so muffler deletes can't be the exact same sound for all years 1.4T. That being said, the muffler delete is around the same db as Abarth 500 stock range.
Well I have a 2011 and the resonator is 2x as long as yours in the pic, odd they changed, I would need to drive a 2013+ to see if I could tell a difference. Either way a [proper muffler change should net a weight loss, gain dB, and not add drone. I guess the Abarth 500 has a 1.4t in it?

I am going to search for a long magnaflow, aeroturbine, dynomax muffler for mine.
 

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Well I have a 2011 and the resonator is 2x as long as yours in the pic, odd they changed, I would need to drive a 2013+ to see if I could tell a difference. Either way a [proper muffler change should net a weight loss, gain dB, and not add drone. I guess the Abarth 500 has a 1.4t in it?

I am going to search for a long magnaflow, aeroturbine, dynomax muffler for mine.
Yes the 500 has a 1.4T but not the same as ours. Was only using it as a reference for sporty loud stock 4 cyl exhaust.

There was a few that others members have used on theirs, some literally went though 3 resonators before finding the one they liked the best.
 
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