2" Exhaust to loud?

[taffstalini]

I have been considering getting a Stage 1 kit for my 998 1989 Mini

I need a new exhaust anyway and the extra parts do not seem too expensive (Huddersfield Spares have a Stage one kit for £129).

Has anyone fitted a full 2" single silencer exhaust system and found it too loud?

If so would a second silencer make any differance?

Also does a cone filter and manifold make a big differance to the noise?

I like the noise the mini makes, its a big part of its character, and would like to amplify it but am concerned that it could be too much and spoil my daily drive/long journeys.

cheers all

[ccharlie6]

is it 2" all the way through (from exhaust manifold onwards?) if so correct me if im wrong but that bore is too big for the 998 and you may find a smaller performance increase than if you use a 1.75" bore system (maniflow etc make good uns)

[cooperman]

A 2" bore on a 998 with a road-going spec will definately result in a loss of power. The velocity of the exhaust gases, which are critical to the overall gas flow of the engine, are in direct proportion to the cross-sectional area of the exhaust pipe. The ideal velocity for a 998 is obtained with a 1.625" or 1.75" diameter pipe with the diameter remaining as neart constant all alnog its length right top the end of the tail pipe, which is why these 3" diameter 'noise booster' tailpipes are power loss creators.
The only time one should use a 2" exhaust on a 998 is on a full-race unit revving to over 7500 rpm and with a cam giving virtually nothing under about 3500 rpm.

[love machine]

I'm inclined to go slightly small with the pipe sizes, my 1380 is running 1.75 ID all the way through (a single box), it aids with heating, extraction and crackles like a beauty! It also stops any gearbox tunnel nightmares.

I ran a 2" system on my last mini with a cherry bomb (all stainless and home made) and it sounded stupid. Do you really want to go deaf? Mine is an earplugs car now!

[tim-d]

There are number of variables to consider here - 2 inch is , as other have pointed out - too big -if after performance , which is after all the whole idea of adding stg 1, lovely noise if thats your thing - beware of cheapo kits though I've never used Huddersfield - stg 1 kits I've had have been from Somerfield (!). As an opionion invest in a decent LCB and slap on a single box RC40 - wouldn't advise a cone filter though, mixture goes extremely weak and never have been convinced that these really keep the crud out of the carb - strictly hearsay but I remeber Calver running a comparative test between cone filter and replacement element with modified standard box - results were if I recall in favour of the replacement element - (some of his articles are on minispares website) I used to run stg 1 of cheapo LCB, Single box RC40 , heated inlet (never convinced by these) and Pipercross Cone - on a centre binnacle instrumented car - exhaust noisy but very pleasant - induction roar very, very loud - probably made worse my removal of rotting bulkhead insulation - went back to replacement element for civilised use - much better - remember though you won't get any benefit from the kit at all unless tuned properly which ideally means rolling road (or my pet genius MG speacialist -Chris Leverett in Clevedon - have no idea what he does as haven't ever stuck around whilst magic goes on - but spot on when put on RR and I know he hasn't got one so a bit of a mystery but I'm not complaining at 30 quid) - budget 60 - 100 for proper set up - later change of any component will alter settings - so cheapo kit sometimes a false economy - get the best your budget will stretch to and you won't go far wrong.....

[Wildfire]

As said above 2" is way too big. I run a Maniflow 1.75" straight through and it makes plenty of noise!!

[Mini1976]

Ive got a 2" maniflow system on my 1275 with cherry bomb and back box. It is very noisy and is not plesant on a long drive. i would have changed it to a 1.75" rc40 if finaces permitted, but the dont at the mo

[mr dann]

By the way, mini****** RC40's look like they have been made by chimps, the bends are as restrictive as can be. Absolute shite, having said, I expect the person who has bought the rights to the RC40 name is rather rich and drives an Aston. The quality is bad, On recieving my kit from this chap, I was disgruntled how anyone could sell such shit. The gibbon they had making my zorst created some spectacular pinches which are by no means good for flow and if the said chap debates this, I will take photos of the bloody thing.

Get something made by a person with a decent pipe bender or do it yourself.

[S works]

Shame that. On my Cooper Spi and my Cooper Mpi S Works, I had Janspeed, Playmini and RC40 SS back boxes mated to various manifolds.

On the highest output engine (the S Works) I found the RC40 to be far better than the Playmini of similar diameter.

The Janspeed (mild steel, regular S Works kit JCG fit) was poor.

My (now ex) girlfriends Mpi Cooper performed superbly with the RC40, fitted approx 18 months ago.

I found the RC40 to be better on all 3 cars. Seems a shame if now they've gone downhill.

[cooperman]

The best system I've had is with a good Maniflow LCB, then a Maniflow 'Cherry Bomb' followed by a centre exit RC40. This is quite quiet and doesn't seem to take out much power. It gives about 93db at 1/2m at 45 deg to exhaust outlet at 5000 rpm, which is OK for the scrutineers. When I just had the complete Maniflow system with the cherry bomb and the Maniflow centre exit box, after a short time the noise was excessive.
Gee, it's bad enough having the noise from the gearbox, the s/c drop gears and the twin 1.5 SU's without a noisy exhaust as well!

[taffstalini]

Thanks for all the comments.

As i am not tuning for pure power (although that would be nice!) I am considering a 1 & 3/4" janspeed manifold and twin box system with DTM style back box (i just like the way it looks).

I use it mostly to get to work and back which means sitting in traffic so all out performance not so critical.

I am still not sure on the K&N style air filter though! Given it will be sitting in traffic i do not know if this will improve things or make it worse.