17 replies to this topic

[MinesRed]

Good evening all.
My 1275 stage 1 mini has a straight through exhaust,could be an RC40 but not sure.
At 3000rpm the noise in the cabin is too much,even with my ear defence.
As a sufferer of tinnitus which is aggrevated by the cabin noise can anyone recommend a decent exhaust,not too loud and one that won't affect the minis performance.
Thanks..

[cal844]

Good evening all.
My 1275 stage 1 mini has a straight through exhaust,could be an RC40 but not sure.
At 3000rpm the noise in the cabin is too much,even with my ear defence.
As a sufferer of tinnitus which is aggrevated by the cabin noise can anyone recommend a decent exhaust,not too loud and one that won't affect the minis performance.
Thanks..

Twin box RC40 system

[gdcarpenter]

For what it's worth: My Mini Mayfair 1000 Genuine 1990 Japanes Cooper conversion, so similar to stage 1.
Had an LCB, gutted CAT, single box RC40 when I got it, couldn't bear the metallic high pitched drone at highway speeds.

Now have stainless steel flex pipe, with an O2 sensor, LCB to the gutted CAT I kept, that may loose me a tiny fraction of HP, but so be it.
That's followed by a 1 3/4" Manjflow twin box, side exit. This set up is not a whole lot quieter, but the tinny high pitch drone is gone. It seems to me the Maniflow seems to be heavier gauge and more solid construction , which. I think, helps reduce the tinniness. It now has a deeper throatier sound that I can live with. The deeper sound may by less aggravating on your tintinitus.

All the best.

[leyland73]

Twin box rc 40, also using the standard air filter box with a k&n filter element is far quieter than a cone filter, less induction noise

[cal844]

Twin box rc 40, also using the standard air filter box with a k&n filter element is far quieter than a cone filter, less induction noise

Yes I agree with using the standard airbox

[evoderby]

Is your current system twin box or single box? Is the exhaust manifold an LCB or cooper type?

 

When it comes to performance without noise a Cooper type manifold fitted with a twin box RC40 side exit is about as good as it gets.   Fitting a turbo quietens things down even further whilst of course increasing performance, at the same time allowing you to select a taller final drive to reduce revs at cruising speeds and further quieten things down. As others have said, don’t overlook the air filter and last but not least dynamat, dynamat, dynamat!

[Anthony30]

maniflow 1.75'' twin box side exit, cooper freeflow manifold. 

[nicklouse]

how old is the current exhaust? side or center exit?

[Wazzah]

Changed from centre exit to side exit which improved the droning.

Pulled the dash the other day and ripped out the factory sound deadening which weighed a tonne and replaced with dynamat.

Improvement.

Dynamated the under of the bonnet.

More improvement.

The engine driven fan annoys me the most and is very loud.

[leyland73]

[quote name="Wazzah" post="3654636" timestamp="1592784618"]Changed from centre exit to side exit which improved the droning.
Pulled the dash the other day and ripped out the factory sound deadening which weighed a tonne and replaced with dynamat.
Improvement.
Dynamated the under of the bonnet.
More improvement.
The engine driven fan annoys me the most and is very loud.[/quote

Great progress so far, what air filter is fitted? Under bonnet sound deadening helps too

[MinesRed]

It's got a manifold lcb manifold and straight through to read centre exit box.
The induction is via a pipercross cone,but I don't mind the sound of that.

[nicklouse]

It's got a manifold lcb manifold and straight through to read centre exit box.
The induction is via a pipercross cone,but I don't mind the sound of that.

most of the noise should be coming from the carb with that set up.

so a single box set up change to a twin box and a side exit is quieter again.

 

and again how old is the silencer as they do blow the wadding out and either replace or repack if you can.

[MinesRed]

It's got a manifold lcb manifold and straight through to read centre exit box.
The induction is via a pipercross cone,but I don't mind the sound of that.

That should read maniflow..

[MinesRed]

Ahh right,so the airfilter contributes to the noise of the exhaust,I honestly didn't think it would,every day n all that...

Edited by MinesRed, 22 June 2020 - 08:53 PM.

[fokko]

I agree to @evoderby. The exhaust pipe and its mufflers don’t contribute that much to interior noise. Most of the noise comes from induction sound (air filter & carb) and the exhaust manifold. The original cast manifold is the most quiet solution. An LCB (http://minispares.co...t/C-AEG365.aspx) is noisier than the Freeflow (http://minispares.co...t/C-STR816.aspx) manifold. Fit some good sound deadening to your bulkhead and decide which compromise you want to make; power or quietness.