Quieter Exhaust

[WIL35]

My recently acquired 4.2 Cerb is decatted and has some sort of Powerflow sports exhaust, which is great fun for short blasts, but is just a bit too loud for longer trips. My original Cerb had a standard exhaust and that suited my need of a GT car.

To get a quieter exhaust, along the lines of the standard set up, is ACT the only option nowadays? I haven't tried it yet, but will putting the cats back in make much difference to the noise with the sports exhaust?

Thanks

[gruffalo]

Yep ACT is about it and it works well.

[morebeanz]

Putting the cats back in does make a modest difference, especially under load, so you might want to try that first, unless you don't like cats.

[Jhonno]

Don't bother putting the cats back in, unless you need a heated gearknob..

You can always get a custom one made for not too much.

Demand Engineering near Ipswich have made a standard style back box for a Cerb before.

[Chimp871]

I'd be interested in what you do. Mines too loud and pop/bang for me.

I have the original exhaust by has some small holes near rear box.

Has anyone had one made? Like to hear details and results.

[spitfire4v8]

I've made quite a few exhausts over the years for the cerbie, but as always with engines which are sensitive to back pressure you've got the conflict of low noise versus high flow. eg the 2.125 inch 4.2 pipes are already a restriction at 360hp. For unrestricted 400plus hp engines you need to be looking at 2.5 inch. Don't expect much in the way of sound deadening from bores that big though!

[morebeanz]

spitfire4v8 said:

I've made quite a few exhausts over the years for the cerbie, but as always with engines which are sensitive to back pressure you've got the conflict of low noise versus high flow. eg the 2.125 inch 4.2 pipes are already a restriction at 360hp. For unrestricted 400plus hp engines you need to be looking at 2.5 inch. Don't expect much in the way of sound deadening from bores that big though!

Presumably that needs to be from the manifolds too to be effective?

[WIL35]

Jhonno said:

Demand Engineering near Ipswich have made a standard style back box for a Cerb before.

Thanks. I will get in contact with them.

[ukkid35]

I was lucky to find what appears to be a Silverstone Performance exhaust

An amazing improvement on the headache inducing Sports Tails, but it does add a little weight

I can get past most track day noise tests now, and if needs be I can add extra baffles in the unfeasibly large tail pipes

https://www.pistonheads.com/gassing/topic.asp?h=0&...

[A and K Cerbera]

Hi
We have an ACT big bore quiet system that we would sell.



PM us if you are interested

[Byker28i]

Similar to what I have. The big bore was 3"? mine is 2.5", so Jules Jules said it was strangling a little power


mine runs 106db at 4.5k revs (well did before the engine

Cats add around 8-10db of noise deadening, but it heats the tunnel/cabin/gearbox/clutch.

[A and K Cerbera]

Our system is 2 1/4" system with 3" silenced tail pipes

[Chimp871]

ukkid35 said:

I was lucky to find what appears to be a Silverstone Performance exhaust

An amazing improvement on the headache inducing Sports Tails, but it does add a little weight

I can get past most track day noise tests now, and if needs be I can add extra baffles in the unfeasibly large tail pipes

https://www.pistonheads.com/gassing/topic.asp?h=0&...

Not sure they're still around.

I just can't see how decatted nodded exhausts get past track day limits. Castle Coombe is 99db static 4000 rom, and my chim450 standard exhaust with cats was 97db

[WIL35]

A and K Cerbera said:

PM us if you are interested

Hi, I'm getting a message saying 'the recipient doesn't receive emails'

[A and K Cerbera]

I have PM you, please confirm.
Don't know why I could not receive your message.

[Byker28i]

Chimp871 said:

I just can't see how decatted nodded exhausts get past track day limits. Castle Coombe is 99db static 4000 rom, and my chim450 standard exhaust with cats was 97db

My car is 106db, I can get it down to 98db with trackday cans fitted to the rear.

[gruffalo]

Byker28i said:

Chimp871 said:

I just can't see how decatted nodded exhausts get past track day limits. Castle Coombe is 99db static 4000 rom, and my chim450 standard exhaust with cats was 97db

My car is 106db, I can get it down to 98db with trackday cans fitted to the rear.

Mine is act balanced headers, decat large bore pipes feeding the ACT quiet back box, 96db or 88db with track cans on.

[Jhonno]

gruffalo said:

Byker28i said:

Chimp871 said:

I just can't see how decatted nodded exhausts get past track day limits. Castle Coombe is 99db static 4000 rom, and my chim450 standard exhaust with cats was 97db

My car is 106db, I can get it down to 98db with trackday cans fitted to the rear.

Mine is act balanced headers, decat large bore pipes feeding the ACT quiet back box, 96db or 88db with track cans on.

The Church mouse of Cerbs..