Mufflers: Borla vs Magnaflow+Resonator
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- TurboRagtop
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Re: Mufflers: Borla vs Magnaflow+Resonator
Great info from Magnaflow engineer. Did you discuss pros and cons of placing the resonator first vs. the muffler first? I would love to hear the engineering reasons why one configuration or the other is better for power, tone or exhaust flow.
Karl Payne, Gilbert, AZ
1966 1600 roadster, 2.3L EFI Turbo Ford engine, FMIC, 2.5" exhaust, T-5 trans, 300ZX big brakes, stand-alone Megasquirt ECU/TunerStudio
1966 1600 roadster, 2.3L EFI Turbo Ford engine, FMIC, 2.5" exhaust, T-5 trans, 300ZX big brakes, stand-alone Megasquirt ECU/TunerStudio
- Alvin
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Re: Mufflers: Borla vs Magnaflow+Resonator
I can do that!Pjackb wrote: Alvin,
If you can measure length and width I can get Karl the part numbers
Alvin Gogineni
San Jose, CA
1967.5 SPL/SR20
1997 Acura Integra GS-R
2022 Chevy Bolt EUV
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San Jose, CA
1967.5 SPL/SR20
1997 Acura Integra GS-R
2022 Chevy Bolt EUV
zcarblog.com
YouTube
My SR20 Build Thread
- Alvin
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Re: Mufflers: Borla vs Magnaflow+Resonator
Muffler dimensions:
17 -3/4" length, 10" width
Resonator dimensions:
14" length, 5" diameter
17 -3/4" length, 10" width
Resonator dimensions:
14" length, 5" diameter
Alvin Gogineni
San Jose, CA
1967.5 SPL/SR20
1997 Acura Integra GS-R
2022 Chevy Bolt EUV
zcarblog.com
Instagram
YouTube
My SR20 Build Thread
San Jose, CA
1967.5 SPL/SR20
1997 Acura Integra GS-R
2022 Chevy Bolt EUV
zcarblog.com
YouTube
My SR20 Build Thread
- TurboRagtop
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Re: Mufflers: Borla vs Magnaflow+Resonator
Thanks Alvin!
Karl Payne, Gilbert, AZ
1966 1600 roadster, 2.3L EFI Turbo Ford engine, FMIC, 2.5" exhaust, T-5 trans, 300ZX big brakes, stand-alone Megasquirt ECU/TunerStudio
1966 1600 roadster, 2.3L EFI Turbo Ford engine, FMIC, 2.5" exhaust, T-5 trans, 300ZX big brakes, stand-alone Megasquirt ECU/TunerStudio
- Pjackb
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Re: Mufflers: Borla vs Magnaflow+Resonator
Karl,
from what we can see in the pictures it looks like Alvin is still running 3" pipes all the way back from the muffler
Since you're running a mild Duractec Turbo I would think that you would want to stay 2.5" all the way so based on the dimension provided by Alvin you would want to go with a Magnaflow 11256 Center/Offset 2.5" muffler and a Magnaflow 12866 5" muffler/resonator , both of these are also available polished but they really don't look that good in polished form
from what we can see in the pictures it looks like Alvin is still running 3" pipes all the way back from the muffler
Since you're running a mild Duractec Turbo I would think that you would want to stay 2.5" all the way so based on the dimension provided by Alvin you would want to go with a Magnaflow 11256 Center/Offset 2.5" muffler and a Magnaflow 12866 5" muffler/resonator , both of these are also available polished but they really don't look that good in polished form
- TurboRagtop
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Re: Mufflers: Borla vs Magnaflow+Resonator
Thanks Pjackb, much appreciated.
Karl Payne, Gilbert, AZ
1966 1600 roadster, 2.3L EFI Turbo Ford engine, FMIC, 2.5" exhaust, T-5 trans, 300ZX big brakes, stand-alone Megasquirt ECU/TunerStudio
1966 1600 roadster, 2.3L EFI Turbo Ford engine, FMIC, 2.5" exhaust, T-5 trans, 300ZX big brakes, stand-alone Megasquirt ECU/TunerStudio
- TurboRagtop
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Re: Mufflers: Borla vs Magnaflow+Resonator
So I finally got my exhaust system put together. I went with a 2 1/2 inch system, a 14 inch Magnaflow, over the rear axle and a 5 inch resonator out back. Finished it off with a megaphone tip. Very happy with how it looks, sounds and performs.
I’m actually going to bring it to Solvang this year.
Thanks everyone for your help, thanks to Michael Spreadbury for instructions on the 4 in. square tubing through the X-member, and special thanks to Alvin for the pictures and dimensions.
Great support here!
I’m actually going to bring it to Solvang this year.
Thanks everyone for your help, thanks to Michael Spreadbury for instructions on the 4 in. square tubing through the X-member, and special thanks to Alvin for the pictures and dimensions.
Great support here!
Karl Payne, Gilbert, AZ
1966 1600 roadster, 2.3L EFI Turbo Ford engine, FMIC, 2.5" exhaust, T-5 trans, 300ZX big brakes, stand-alone Megasquirt ECU/TunerStudio
1966 1600 roadster, 2.3L EFI Turbo Ford engine, FMIC, 2.5" exhaust, T-5 trans, 300ZX big brakes, stand-alone Megasquirt ECU/TunerStudio
- Linda
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Re: Mufflers: Borla vs Magnaflow+Resonator
How about a pic? Did you use a stock megaphone or an aftermarket?
Linda
Linda
Sadly-Linda has passed away 2022. She was the 311's den mother and drove the first Rare-Parts ball joint project. RIP.
- TurboRagtop
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Re: Mufflers: Borla vs Magnaflow+Resonator
I went with a generic megaphone tip ordered online. I’ll work on some pics of the installation but it will be a while since I’m traveling.
Karl Payne, Gilbert, AZ
1966 1600 roadster, 2.3L EFI Turbo Ford engine, FMIC, 2.5" exhaust, T-5 trans, 300ZX big brakes, stand-alone Megasquirt ECU/TunerStudio
1966 1600 roadster, 2.3L EFI Turbo Ford engine, FMIC, 2.5" exhaust, T-5 trans, 300ZX big brakes, stand-alone Megasquirt ECU/TunerStudio
- TurboRagtop
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Re: Mufflers: Borla vs Magnaflow+Resonator
Rear shots of megaphone tip.
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Karl Payne, Gilbert, AZ
1966 1600 roadster, 2.3L EFI Turbo Ford engine, FMIC, 2.5" exhaust, T-5 trans, 300ZX big brakes, stand-alone Megasquirt ECU/TunerStudio
1966 1600 roadster, 2.3L EFI Turbo Ford engine, FMIC, 2.5" exhaust, T-5 trans, 300ZX big brakes, stand-alone Megasquirt ECU/TunerStudio
- RCMike
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Re: Mufflers: Borla vs Magnaflow+Resonator
You will want to slice that on an angle towards the wheels for better clearance, as you head in and out of driveways.. Or it will shortly have a flat bottom, or at least I did..
- TurboRagtop
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Re: Mufflers: Borla vs Magnaflow+Resonator
Thanks Mike, I’ll test the setup on some steep driveways and check the clearance.
Karl Payne, Gilbert, AZ
1966 1600 roadster, 2.3L EFI Turbo Ford engine, FMIC, 2.5" exhaust, T-5 trans, 300ZX big brakes, stand-alone Megasquirt ECU/TunerStudio
1966 1600 roadster, 2.3L EFI Turbo Ford engine, FMIC, 2.5" exhaust, T-5 trans, 300ZX big brakes, stand-alone Megasquirt ECU/TunerStudio
- Linda
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Re: Mufflers: Borla vs Magnaflow+Resonator
If you trash that one, here is another option, just cut and weld:
https://m.ebay.com/itm/VW-Beetle-CHROME ... SwcUBYQD8O
Linda
https://m.ebay.com/itm/VW-Beetle-CHROME ... SwcUBYQD8O
Linda
Sadly-Linda has passed away 2022. She was the 311's den mother and drove the first Rare-Parts ball joint project. RIP.
- TurboRagtop
- Roadster Nut-Site Supporter
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Re: Mufflers: Borla vs Magnaflow+Resonator
Thanks Linda, good tip! See what I did there... 
Karl Payne, Gilbert, AZ
1966 1600 roadster, 2.3L EFI Turbo Ford engine, FMIC, 2.5" exhaust, T-5 trans, 300ZX big brakes, stand-alone Megasquirt ECU/TunerStudio
1966 1600 roadster, 2.3L EFI Turbo Ford engine, FMIC, 2.5" exhaust, T-5 trans, 300ZX big brakes, stand-alone Megasquirt ECU/TunerStudio
- ppeters914
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Re: Mufflers: Borla vs Magnaflow+Resonator
Any chance you made a recording, or does it sound similar to Alvin's?TurboRagtop wrote: Fri Jan 05, 2018 9:25 am So I finally got my exhaust system put together. I went with a 2 1/2 inch system, a 14 inch Magnaflow, over the rear axle and a 5 inch resonator out back. Finished it off with a megaphone tip. Very happy with how it looks, sounds and performs.
I was wondering how you got 2-1/2 inch pipe through. I was test fitting a 2-inch on mine, and no way without flattening it 1/16-inch or more.TurboRagtop wrote: Fri Jan 05, 2018 9:25 am Thanks everyone for your help, thanks to Michael Spreadbury for instructions on the 4 in. square tubing through the X-member, and special thanks to Alvin for the pictures and dimensions.
Pete
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'67 1600 - frame off started in 2014. Now I know why roadster projects take so long. What a stupid idea.
'66 1600 - parts car
'66 WPL411 ***SOLD***
A couple of Porsches, a RAV4 Hybrid, and a motorcycle
-------------------------------------
'67 1600 - frame off started in 2014. Now I know why roadster projects take so long. What a stupid idea.

'66 1600 - parts car
'66 WPL411 ***SOLD***
A couple of Porsches, a RAV4 Hybrid, and a motorcycle