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Ade

My Custom Hayward and Scott Cat-Back Design and Proving

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14 minutes ago, S18 RSG said:

Well, the thread is about the volume of exhausts. I think many people would be surprised to hear that an unsilenced, uncatted exhaust system on a turbo car is perfectly livable, whereas a supercharged car may require a lot of extra silencing. I saw that more as useful consumer advice than point scoring.

I'm not that much of a dick that I'll find any opportunity to belittle your opinion or choice, just trying to make a useful contribution :)

I actually thought t it was common knowledge!

Everyone has different levels of tolerance/desire for noise. I dont want to hear anything more than a mild burble wot at 3krpms, the sort of level you have to listen for rather than be forced to hear it. 

Plenty of people couldn't see what I was complaining about with my last cat back which was 92dB@5k. Certainly with the stock cat back its very quiet, but everywhere which is not what I wanted. Also small piping. 

The Cossy SC adds approx 3dB to the standard noise test at 5k rpms over N/A. Higher power from the SC will add more. More flow = More noise.

 

 

 

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Don't think I've ever been out in your car on the road, but on track the new H&S kit pre-resonator was a lot more comfortable than the Cosworth catback but still suited the car very well. I know exactly what you mean with the drone at 3k WOT as it can be an issue when using cruise on a motorway... I think going 1.3 might make this worse  :D

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6 minutes ago, Steeps said:

Don't think I've ever been out in your car on the road, but on track the new H&S kit pre-resonator was a lot more comfortable than the Cosworth catback but still suited the car very well. I know exactly what you mean with the drone at 3k WOT as it can be an issue when using cruise on a motorway... I think going 1.3 might make this worse  :D

I think it should be possible to fit the Helmholtz Resonators to the cossy system. I've asked Ian for a price for that. 

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Given on mostly 4.5K-redline being most common on track (and where i'd want extra roar to hear), imho quietening below 3K is wise move. Should also quieten cold starts with no tune mods at all.

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You should pop this on FT86 forum too, Ade. People/companies have gone to great lengths to get a catback which is high flow but also livable, and passes noise restrictions. (The ACE/CSG catback as an example). So if you've achieved it then put it out there!

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You should pop this on FT86 forum too, Ade. People/companies have gone to great lengths to get a catback which is high flow but also livable, and passes noise restrictions. (The ACE/CSG catback as an example). So if you've achieved it then put it out there!

I dont think it will be that quiet with a catless manifold and frontpipe. Leguna Seca is very strict.... and you see stuff like this 😂33ae65052dbce93ff000ff36bc22ae80.jpg

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17 minutes ago, Adam9 said:

Did you manage to get any info on what they would charge to do another one of these yet Ade?

Yes mate.

So pricing looks like this:

  • Cat-Back with 70mm piping and the extra larger center silencer £650 + VAT 
  • Exhaust Tips of your choice: Varies but roughtly ~£75+VAT
  • Helmholtz Resonators: £275+VAT

Above priced are fitted

Please note this system differs from their standard offerings in that it has 70mm pipe diameter and the extra larger middle box is bigger than their "larger center silencer" on their website. 

If in doubt talk to Ian at H&S about your needs.

 

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9 minutes ago, Adam9 said:

Thanks mate, not cheap but still looks like pretty good value

H&S are not the cheapest but their quality is top notch and comes with a lifetime warranty (subject to their conditions).

 

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Hey Ade, would you mind sharing the specs for the resonators ? 

Wondering if I could attach them to an HKS Hi-Power Spec-L that has the same issue you had, boomy at WOT around 3k, especially when combined with a Tomei decat EL manifold that seems to seriously increase those frequencies.  The HKS is differentand the specs would help me figure out if they would fit.

Cheers,

Adi

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Hey Ade, would you mind sharing the specs for the resonators ? 
Wondering if I could attach them to an HKS Hi-Power Spec-L that has the same issue you had, boomy at WOT around 3k, especially when combined with a Tomei decat EL manifold that seems to seriously increase those frequencies.  The HKS is differentand the specs would help me figure out if they would fit.
Cheers,
Adi
Hi Adi, pop me a PM and can discuss. Just recently I helped a guy with his cobra. We had to modify the dimensions a bit but the target frequency was the same and worked a treat just with one resonator chamber.

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