SOUL | 718 GT4/Spyder Exhaust Development
#676
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John, thanks for the reply and I think we are actually pretty close to on the same page.
I need to clarify my comment because apparently context is important. When I say “race exhaust” I mean one specially designed to provide maximum performance for its individual application. It has one, and only one purpose, to maximize performance within the parameters of the race class it’s being developed for. It starts at the exhaust port and ends at the tail pipe. I didn’t mean a cat back system, regardless what it’s called, I was referring to the completely open competition system being described above.
Take that system and put cats on it or as described above, use the rear section on the factory headers and that changes the equation. While most of them would be louder than what I want on a primarily street car I can see where some would like it, especially if it was tuned and not simply straight pipes.
I’ve been around race cars my entire life, literally since I was born so I’ve pretty much heard it all from top fuel funny cars to V12 F1 motors. I love the sounds of a purpose built race motor at full song but there’s a time and place for that noise and it’s rarely on neighborhood streets.
I need to clarify my comment because apparently context is important. When I say “race exhaust” I mean one specially designed to provide maximum performance for its individual application. It has one, and only one purpose, to maximize performance within the parameters of the race class it’s being developed for. It starts at the exhaust port and ends at the tail pipe. I didn’t mean a cat back system, regardless what it’s called, I was referring to the completely open competition system being described above.
Take that system and put cats on it or as described above, use the rear section on the factory headers and that changes the equation. While most of them would be louder than what I want on a primarily street car I can see where some would like it, especially if it was tuned and not simply straight pipes.
I’ve been around race cars my entire life, literally since I was born so I’ve pretty much heard it all from top fuel funny cars to V12 F1 motors. I love the sounds of a purpose built race motor at full song but there’s a time and place for that noise and it’s rarely on neighborhood streets.
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ZZebes (01-22-2021)
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Soul Performance (01-26-2021)
#680
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Hey John,
sorry if this has been addressed in this thread but is the Akra OAP compatible with your valved exhaust muffler?
thanks
sorry if this has been addressed in this thread but is the Akra OAP compatible with your valved exhaust muffler?
thanks
#681
Burning Brakes
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If Akra states their OAP is compatible with the OEM valved muffler, and Soul's muffler is directly interchangeable with the OEM muffler, then by transitive property they are compatible.
Akra OAP <-> OEM Muffler
Soul Muffler <-> OEM Muffler
Therefore
Akra OAP <-> Soul Muffler
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neurotic (01-26-2021)
#682
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These two if you buy their headers you also need their OAP. Klein inverted the path of the exhaust from what I read here.
The others have a modular design that's is pretty much interchangeable with each others.
#683
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All 3 parts in the system are interchangeable. Every manufacturer is making all 3 parts (headers, OAP, and muffler) individually purchasable and interchangeable. The only issue you'd have is if you tried to use the OAP from Soul's Race exhaust (1x2.5" outlet) with a different muffler (2x2.25" inlets).
If Akra states their OAP is compatible with the OEM valved muffler, and Soul's muffler is directly interchangeable with the OEM muffler, then by transitive property they are compatible.
Akra OAP <-> OEM Muffler
Soul Muffler <-> OEM Muffler
Therefore
Akra OAP <-> Soul Muffler
If Akra states their OAP is compatible with the OEM valved muffler, and Soul's muffler is directly interchangeable with the OEM muffler, then by transitive property they are compatible.
Akra OAP <-> OEM Muffler
Soul Muffler <-> OEM Muffler
Therefore
Akra OAP <-> Soul Muffler
Not all of them...the BC Exhaust recently posted uses a V-band connection from header to a very specific OAP...it does connect to the OEM muffler. Dundon has a similar design.
These two if you buy their headers you also need their OAP. Klein inverted the path of the exhaust from what I read here.
The others have a modular design that's is pretty much interchangeable with each others.
These two if you buy their headers you also need their OAP. Klein inverted the path of the exhaust from what I read here.
The others have a modular design that's is pretty much interchangeable with each others.
Yes, the Akra OAP's are bolt on compatible with our Valved Exhaust System. All our components are modular and interchangeable with our own products or others you may already have on the car that are bolting up to the factory components ours replace. The only exception to the is our Race Exhaust that cannot connect to any other company's over axle pipes, it has a unique design from the header flange to the exhaust tips.
Best regards,
John Gaydos
__________________
SOUL PERFORMANCE PRODUCTS
Quality Exhaust Solutions, Fair Pricing, and Outstanding Service
John Gaydos- Owner, Performance Specialist
Cell - (484) 883-6197
johng@soulpp.com
Jon Wheel - Marketing Manager
jwheel@soulpp.com
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SOUL PERFORMANCE PRODUCTS
Quality Exhaust Solutions, Fair Pricing, and Outstanding Service
John Gaydos- Owner, Performance Specialist
Cell - (484) 883-6197
johng@soulpp.com
Jon Wheel - Marketing Manager
jwheel@soulpp.com
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neurotic (01-26-2021)
#684
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Hello all, new to the forum and it seems there are lot to learn from here.
Just paid for the soul race exhaust through the local garage and I will try to do a before and after dyno based on our Canadian fuel.
Cheers!
Just paid for the soul race exhaust through the local garage and I will try to do a before and after dyno based on our Canadian fuel.
Cheers!
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Soul Performance (01-26-2021)
#685
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Ok just had my race exhaust installed and drove probably 50 miles with it on so far.
Let’s get this out of the way... it’s WAY louder and better sounding than stock. I love it. It will definitely be too obnoxious for some people, and there’s also noticeable drone from about 2k -2800 as others have stated. But for me it’s not nearly as bad as other systems I’ve heard, and also it’s very simple to drive above that range. Even highway, 65 in 5th is above it and 75+ in 6th is above that range and is totally fine. Like even people sensitive to drone shouldn’t be bothered by it at those highway speeds.
It’s hard for me to imagine how this would sound with cat deletes/sport cats, but I may have to sign up for the sport cats when they’re available![rockon](https://rennlist.com/forums/graemlins/rockon.gif)
Quick question for John/Mike - I noticed when I was driving in a parking garage at low rpm there’s an intake sound that sounds like it’s coming from the exhaust area (hard to tell since I was driving) but I only hear it when DECELERATING from a low rpm. So maybe 15mph to 7mph in 1st. Does this seem normal? Or is it possible that the install didn’t plug the vacuum lines or something?
Let’s get this out of the way... it’s WAY louder and better sounding than stock. I love it. It will definitely be too obnoxious for some people, and there’s also noticeable drone from about 2k -2800 as others have stated. But for me it’s not nearly as bad as other systems I’ve heard, and also it’s very simple to drive above that range. Even highway, 65 in 5th is above it and 75+ in 6th is above that range and is totally fine. Like even people sensitive to drone shouldn’t be bothered by it at those highway speeds.
It’s hard for me to imagine how this would sound with cat deletes/sport cats, but I may have to sign up for the sport cats when they’re available
![rockon](https://rennlist.com/forums/graemlins/rockon.gif)
Quick question for John/Mike - I noticed when I was driving in a parking garage at low rpm there’s an intake sound that sounds like it’s coming from the exhaust area (hard to tell since I was driving) but I only hear it when DECELERATING from a low rpm. So maybe 15mph to 7mph in 1st. Does this seem normal? Or is it possible that the install didn’t plug the vacuum lines or something?
#686
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Ok just had my race exhaust installed and drove probably 50 miles with it on so far.
Let’s get this out of the way... it’s WAY louder and better sounding than stock. I love it. It will definitely be too obnoxious for some people, and there’s also noticeable drone from about 2k -2800 as others have stated. But for me it’s not nearly as bad as other systems I’ve heard, and also it’s very simple to drive above that range. Even highway, 65 in 5th is above it and 75+ in 6th is above that range and is totally fine. Like even people sensitive to drone shouldn’t be bothered by it at those highway speeds.
It’s hard for me to imagine how this would sound with cat deletes/sport cats, but I may have to sign up for the sport cats when they’re available![rockon](https://rennlist.com/forums/graemlins/rockon.gif)
Quick question for John/Mike - I noticed when I was driving in a parking garage at low rpm there’s an intake sound that sounds like it’s coming from the exhaust area (hard to tell since I was driving) but I only hear it when DECELERATING from a low rpm. So maybe 15mph to 7mph in 1st. Does this seem normal? Or is it possible that the install didn’t plug the vacuum lines or something?
Let’s get this out of the way... it’s WAY louder and better sounding than stock. I love it. It will definitely be too obnoxious for some people, and there’s also noticeable drone from about 2k -2800 as others have stated. But for me it’s not nearly as bad as other systems I’ve heard, and also it’s very simple to drive above that range. Even highway, 65 in 5th is above it and 75+ in 6th is above that range and is totally fine. Like even people sensitive to drone shouldn’t be bothered by it at those highway speeds.
It’s hard for me to imagine how this would sound with cat deletes/sport cats, but I may have to sign up for the sport cats when they’re available
![rockon](https://rennlist.com/forums/graemlins/rockon.gif)
Quick question for John/Mike - I noticed when I was driving in a parking garage at low rpm there’s an intake sound that sounds like it’s coming from the exhaust area (hard to tell since I was driving) but I only hear it when DECELERATING from a low rpm. So maybe 15mph to 7mph in 1st. Does this seem normal? Or is it possible that the install didn’t plug the vacuum lines or something?
Regards,
John Gaydos
#688
Burning Brakes
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Jim Rockford (01-26-2021)
#690
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Thanks very much for the feedback, it's right in line with all the experiences thus far. And yes, that sound at very low speed/low rpm deceleration is perfectly normal. I'd almost describe it as a growl/exhale, and it is generated by the blending of the exhaust flow in the X-Pipe and is shared by every exhaust system we've developed that merges the exhaust flow with an X in the system. Good ear by the way, not many people have picked up on that haha.
Regards,
John Gaydos
Regards,
John Gaydos
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