10 replies to this topic

[Harrison541]

When I bought the car it came with a rusty & cracked manifold and straight through pipe but a stainless 2.5" backbox.

 

I replaced them with an LCB and a stainless straight through centre pipe, but kept the 2.5" backbox as it was in good condition and a new one would cost me around £100.

 

Now though, I want to quieten down my Mini and so i was wondering if replacing the 2.5" box with the correct 1.75" box would make much difference to the noise?

[lsto]

Would quieten it down but you'll prob have a slight loss in performance, also I'm not 100% positive but I don't think the standard exhaust will fit on the LCB. Your probabily better off removing the straight through pipe and fitting a twin box system. I have the same problem on my cooper, it has a stainless system with just a back box, sounds nice but its sooooooooooo loud on a long journey.

I was gonna treat myself to a twin box system after Christmas...

[minidaves]

check the timinig is correct this will reduce exhaust noise, or fit a muffler

[HarrysMini]

Would quieten it down but you'll prob have a slight loss in performance, also I'm not 100% positive but I don't think the standard exhaust will fit on the LCB. Your probabily better off removing the straight through pipe and fitting a twin box system. I have the same problem on my cooper, it has a stainless system with just a back box, sounds nice but its sooooooooooo loud on a long journey.

I was gonna treat myself to a twin box system after Christmas...

 

 

 

 

You won't have a loss in performance, more like a gain in performance.

Edited by HarrysMini, 15 December 2013 - 12:49 PM.

[cal844]

 

Would quieten it down but you'll prob have a slight loss in performance, also I'm not 100% positive but I don't think the standard exhaust will fit on the LCB. Your probabily better off removing the straight through pipe and fitting a twin box system. I have the same problem on my cooper, it has a stainless system with just a back box, sounds nice but its sooooooooooo loud on a long journey.

I was gonna treat myself to a twin box system after Christmas...

 

 

 

 

You won't have a loss in performance, more like a gain in performance.

 

 

yes by a fair amount

[Harrison541]

but to what extent would it reduce the noise?

[Harrison541]

 

 

Would quieten it down but you'll prob have a slight loss in performance, also I'm not 100% positive but I don't think the standard exhaust will fit on the LCB. Your probabily better off removing the straight through pipe and fitting a twin box system. I have the same problem on my cooper, it has a stainless system with just a back box, sounds nice but its sooooooooooo loud on a long journey.

I was gonna treat myself to a twin box system after Christmas...

 

 

 

 

You won't have a loss in performance, more like a gain in performance.

 

 

yes by a fair amount

 

A performance increase just by changing the back box?

[Tamworthbay]

Indeed, bigger is not always better, especially on exhausts! I would suggest maniflow products as they are superb. I have a single box and don't find it too loud, but obviously a twin box would be quieter.

[jaydee]

To reduce noise, you need to add a little resonator box in the middle

[DomCr250]

You could try restricting the exhaust outlet to 1.75", if it's not got a rolled end then it should be simple to try and fit a restrictor - if the system has no back pressure then it will be loud and also not help your performance much in low and mid range.

 

Basically it's what everybody else says 'the bigger the bore the more noise'

 

Whats the spec of you engine?  A 2.5" bore is a big pipe for any A series mini that's normally aspirated.

[mab01uk]

Fit a twin box RC40 you get the best of both worlds, performance with low noise......long ago proven and tested by David Vizard.

 

"The genuine RC40 system has justifiably earned the reputation of the best exhaust ever made for the Mini. Typically used with an LCB manifold it gives great performance with a mellow sound. 1.75" OD pipe, resonator & silencer ("two-box" system)."

http://www.minispare....aspx?pid=37904

 

RC40 is also available in stainless steel but mild steel exhaust systems are always quieter but not as long lasting.

http://www.minispare...range.aspx?1106

Edited by mab01uk, 15 December 2013 - 01:38 PM.