9 replies to this topic

[akaz_mayfair]

hi,

i have a 1988 998cc mayfair and have recently fitted a stage 1, the exhaust system is a full lcb with branch, through pipe and twin super sport tail pipes, and its just too loud!!!!!!
its missing the classic mini sound,
is a silencer on the staright through pipe the answer???
please dont say baffels as they are too expensive and involve too much hassel too replace,
but will a K+N cone filter make a difference as the air flow is restrcited during induction but the exhaust rams it out
any suggestion???????????????????????
thanks

[Sam Walters]

wont make a diffrence to the noise, personally i would drill the air box and leave a standard panel air filter, not k and n or anything like that just change it regually, it will flow better then a k and n.


i dont see why the exaust noise is a problem its not that loud with pretty much any stage one kit.

ive got a stright through maniflow stage two and thats about as loud as they get. and its fine.

[akaz_mayfair]

wont make a diffrence to the noise, personally i would drill the air box and leave a standard panel air filter, not k and n or anything like that just change it regually, it will flow better then a k and n.


i dont see why the exaust noise is a problem its not that loud with pretty much any stage one kit.

ive got a stright through maniflow stage two and thats about as loud as they get. and its fine.

its just simply too loud,
has anyone out there had this problem

[HARBER07]

Yep. Ive got this problem now with a 2" system, way too big. An RC40 twin box system is about the quietest i think.

[blue redtop]

ive got a twin 3" dtm back box, with a stage 1 kit.ie manifold changed and y piece, 1.75" bore strate through pipe and i want mine louder.its very quiet.

Edited by blue redtop, 23 May 2008 - 09:31 PM.

[blue redtop]

a 2" system is to big for a 998cc.you will be losing power

[HARBER07]

a 2" system is to big for a 998cc.you will be losing power

If you meant me then yes im fully aware a 2" system is too big for a 998. I was just saying a 2" system seems very very noisy. (yes i know loud pedal etc.)

[mini_lad_1990]

i had the same on me old mini i had a straight through twin dtm and it was a mental sound everyone loved it part from my nabours haha

but me being me i have gone for the same syste the pigs can pull me all they like lol my car aint fot to have a cat i will have a silence box this time tho i dnt think it will make much difference but i can say its there imagine it without it lol

i was goin to put it on my 998 prob will as its lieing about doing nothing and my car has a stupid little pee shooter on it haha

cheers

[akaz_mayfair]

ive looked at the rc40 before but could not find a site which sells one, as in iust the through pipe and the centre box (silencer) (mid box) attached,
i wouldnt say a 2" system is too much for a 998 as the back pressure is still strong,

but the main question is where that amazing mini sound actually comes from
is it from the staright cut boxes???

[T.Harper]

ive looked at the rc40 before but could not find a site which sells one, as in iust the through pipe and the centre box (silencer) (mid box) attached,
i wouldnt say a 2" system is too much for a 998 as the back pressure is still strong,

but the main question is where that amazing mini sound actually comes from
is it from the staright cut boxes???

I think you're confusing the straight cut whine of 1st gear with the exhaust pitch...somehow...I think...

A performance exhaust is normally of straight through design, missing baffles and flowing though perforated pipe of a specific diameter, which doesn't hinder flow, removes excess sound and keeps backpressure optimum to reduce the energy the engine spends on 'pumping losses'. Certain systems also go one step further, and they have been developed to actually help scavenge exhaust gas from the cylinder with a combination of pipe diameters and lengths. Two of the best known well flowing mini systems are Maniflow and RC40. RC40 were originally made by competition silencers, and can still be bought from minispares.com in a variety of box combinations, exit locations, tailpipe choices and materials (steel and stainless).

If you have a single box system right now, then yes, changing to a through pipe with a silencer in it, effectively making your single box system a twin box system, will reduce noise. I have however heard a supersport system in the past, and they are very loud compared to more traditional designs.

If it is the transmission whine you are after, it is a much bigger job, involving removing the engine and replacing the standard helical gears for straight cut, and/or the gearset for a straight cut set. This is normally done for higher loading reasons rather than sound, however...

A 2 inch system is over optimum on most 1275s, nevermind a 998. Maniflow and RC40 have a slightly smaller diameter piping, (1.75" or 1 7/8" i can't remember off the top of my head) which improves low end driveability. 2 inch systems are certainly available from maniflow however for large displacement operations such as turbocharged a series.