SOUL | 718 GT4/Spyder Exhaust Development
#736
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Incidentally, my wife is fine with it - she didn't even need to turn her hearing aids off!
#738
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I think this is evidence to support the fact that exhaust drone is an incredibly complex phenomenon. There are obvious solutions for it, the problem is that each of those solutions involves creating flow restrictions. When you want to make an exhaust where you see proper dyno gains by avoiding any kind of restriction you are going to run into drone as a fact of life.
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Soul Performance (03-09-2021)
#739
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I think this is evidence to support the fact that exhaust drone is an incredibly complex phenomenon. There are obvious solutions for it, the problem is that each of those solutions involves creating flow restrictions. When you want to make an exhaust where you see proper dyno gains by avoiding any kind of restriction you are going to run into drone as a fact of life.
This...also the sensitivity of people to drone varies a lot.
I just got my Race exhaust installed over the weekend (will wait a bit more for the headers) and yes, it's loud but the drone I find it Ok and minimal for a race exhaust....it's actually much less than my previous 981 GT4 with a GT3 + race headers exhaust.
You can feel the power gains with this one....I'm actually amazed a N/A car can improve so much with a simple cat back.
I'll take the power gains and improved sound over a quieter/less drone system...I might as well get OPF delete pipes and leave the stock muffler if I wanted that.
Got the Braille Carbon battery also on the car so chopped close to 60 lbs between both.
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Soul Performance (03-09-2021)
#740
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- 2.5" from the headers back without any bottlenecks
- One flow path, so no colliding of the main and secondary path near the end (because the more restrictive path isn't blocked when the valves open there is flow through the large and small path which then doesn't merge so much as run back into itself)
- Crossover pipe
The first two are a big deal I suspect. The X pipe is probably hardly measurable but does make the sound nicer. What would teach us a lot is if we could see the race exhaust dyno'd against the valved solution w/ the split OAP.
It's annoying that this "ideal" and very affordable solution for power becomes totally unlivable once you add (race) headers to it. Though adding some sport cats near the end of the OAP wouldn't be too hard I suppose.
#741
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Obvious improvements to performance from the "race" exhaust, in my opinion:
- 2.5" from the headers back without any bottlenecks
- One flow path, so no colliding of the main and secondary path near the end (because the more restrictive path isn't blocked when the valves open there is flow through the large and small path which then doesn't merge so much as run back into itself)
- Crossover pipe
The first two are a big deal I suspect. The X pipe is probably hardly measurable but does make the sound nicer. What would teach us a lot is if we could see the race exhaust dyno'd against the valved solution w/ the split OAP.
It's annoying that this "ideal" and very affordable solution for power becomes totally unlivable once you add (race) headers to it. Though adding some sport cats near the end of the OAP wouldn't be too hard I suppose.
- 2.5" from the headers back without any bottlenecks
- One flow path, so no colliding of the main and secondary path near the end (because the more restrictive path isn't blocked when the valves open there is flow through the large and small path which then doesn't merge so much as run back into itself)
- Crossover pipe
The first two are a big deal I suspect. The X pipe is probably hardly measurable but does make the sound nicer. What would teach us a lot is if we could see the race exhaust dyno'd against the valved solution w/ the split OAP.
It's annoying that this "ideal" and very affordable solution for power becomes totally unlivable once you add (race) headers to it. Though adding some sport cats near the end of the OAP wouldn't be too hard I suppose.
Agreed....., specially the second one, I wanted a simple, single path exhaust to maximize power.
Guess you could modify the Race OAP with some HJS cats. I have the race headers in standby right now.....my guess the overall volume will go up but mostly at WOT, will try them anyway in a few weeks.
#742
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alwaysdriving (03-09-2021)
#743
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And ^^^ that's exactly one major reason I'm leaving the Porsche Factory Exhaust on mine.
I've been down that road many-many times in the past and this time I'm Not going down it !!!
Terry
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If you heard the Spyder I drove last week with the Soul Race exhaust I think you would change your mind...it sounded awesome, and I ordered a Spyder the next day.
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Soul Performance (03-09-2021)
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Agreed....., specially the second one, I wanted a simple, single path exhaust to maximize power.
Guess you could modify the Race OAP with some HJS cats. I have the race headers in standby right now.....my guess the overall volume will go up but mostly at WOT, will try them anyway in a few weeks.
Guess you could modify the Race OAP with some HJS cats. I have the race headers in standby right now.....my guess the overall volume will go up but mostly at WOT, will try them anyway in a few weeks.
#746
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Agreed....., specially the second one, I wanted a simple, single path exhaust to maximize power.
Guess you could modify the Race OAP with some HJS cats. I have the race headers in standby right now.....my guess the overall volume will go up but mostly at WOT, will try them anyway in a few weeks.
Guess you could modify the Race OAP with some HJS cats. I have the race headers in standby right now.....my guess the overall volume will go up but mostly at WOT, will try them anyway in a few weeks.
And to address the last comment, we all know others make some of these as well but Soul does it just as well, if not better in cases, and their customer service is second to none so I am not sure why someone would look elsewhere.
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#747
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Cool.
#748
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Well, yes. But if you look at the price of the Soul race exhaust and add the cost of two HJS cores (say $1K to 1200) and a bit of welding from a shop (couple hundred) you're still only like halfway to the cost of some of the other offerings. And clearly the Soul solution makes very good power to begin with.
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#749
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Well, yes. But if you look at the price of the Soul race exhaust and add the cost of two HJS cores (say $1K to 1200) and a bit of welding from a shop (couple hundred) you're still only like halfway to the cost of some of the other offerings. And clearly the Soul solution makes very good power to begin with.
Last edited by TDT; 03-08-2021 at 12:06 PM.