I am seeing more and more pod filters and cone type filters on minis, mostly injection. I thought I would make a little post to explain why this is not a particularly good idea… Firstly if styling comes before power to you then maybe it’s not so bad, but technically speaking, the common cone filters that you see sit right in top of the injection air intake and therefore take up less space etc.. But Many people do this for any possible performance gain and frankly if does the opposite! The standard air box has a pipe aimed forwards to pick up air from a cooler part of what Is a very warm engine bay, this also means it gets a little more fresh cool air from the front when the car is moving… The theory here is that cool air is more dense and more air can fit into the same space (this is why compressors work more efficiency in the colder months) depending on the level of tune your engine is in the density of the air going in probably won’t make that much difference, but it still goes to say that the cone filters that fit right over the air intake on one of the warmer parts if the engine bay can’t help with performance, this is why any serious tuner will use a cold air intake when trying to get every bit of power they can from an engine! So please, save yourself some money on doing more harm than good here, the factory air box is quite adequate for the job, use a free flowing filter if it makes you feel better but that’s all you really need to do!
Agree!
My SPI is running a lot better with the K&N element V the 57i induction kit! Generally speaking but pulling through the gears is smoother and there’s more power at the top end!
It’s ok if you like the noise but I’ve just turned the stereo up instead.
I have often wondered that. I have the new Cooper ‘S’ MPI kit and it uses the K&N filter. I don’t like the look of it, or the sucking noise it makes. I may go back to the standard bo (also with a K&N) and see if it makes any difference.
I did have it on the rolling road and the kit with the K&N filter on the top has given me 84BHP & 96Lbs torque
Q
Problem with the filter box is heat soak and it is massively restrictive for big power.
Proper K & N kits come with a length of hose for just the problem you describe. This is to direct cooler air to the cone.
To be honest since a mini isn’t the most streamlined design, plenty air will be being forced through the front grill and around the engine. (Less so in an MPi for reasons of the radiator).
I swapped my K & N cone for a filter box with K & N internal filter, because I was fed up with the induction roar. Car drives better and anyway you can mod the standard box to flow better
FS
Air Cooler ducts, just think what does a normal carb filter do. Can assure you with the ITG kit and air ducts you notice the difference vs the airbox.
And as for the induction roar.. ;wub: how can you not love it? 
The standard air box has a pick up for hot air from the manifold, its not uncommon for them to jam open and you are always picking hot air from below.
The only actual problem of KN cone vs standard air box, is the poor design of the cone which requires (a very simple) modification to stay ‘solid’ in place and to stop it falling off every then and now.
Induction noise is a personal preference, some may love it, some hate it.
The standard air box has a pick up for hot air from the manifold, its not uncommon for them to jam open and you are always picking hot air from below.
The only actual problem of KN cone vs standard air box, is the poor design of the cone which requires (a very simple) modification to stay ‘solid’ in place and to stop it falling off every then and now.
Induction noise is a personal preference, some may love it, some hate it.
In the SPi, yes. MPi is a different/better design.
ITG or RAMAIR foam filters with baseplates work just fine. Cone filters or mesh covered filters run hotter as the metal gets hot. JCG used ITG successfully, I used RAMAIR with a ram pipe, all good.
How come no one makes a desent enclosed type filter/housing? Surely there’s enough minis of the newer type (spi/mpi) to make it worth while.
How come no one makes a desent enclosed type filter/housing? Surely there’s enough minis of the newer type (spi/mpi) to make it worth while.
agreed! I think that the best thing to do for injection cars at the minute is to use the K&N filter that fits in the standard air box - these filters flow far better than standard filters, this is by having larger holes in the filter, but they have lots of little whiskers that catch the muck that gets through, similar to how nose hairs work! (ewww) this should manage to get any cooler air available into the engine and with the benefits of a free flowing filter? correct if I’m wrong on any of this!
peter-b wrote:
How come no one makes a desent enclosed type filter/housing? Surely there’s enough minis of the newer type (spi/mpi) to make it worth while.
agreed! I think that the best thing to do for injection cars at the minute is to use the K&N filter that fits in the standard air box - these filters flow far better than standard filters, this is by having larger holes in the filter, but they have lots of little whiskers that catch the muck that gets through, similar to how nose hairs work! (ewww) this should manage to get any cooler air available into the engine and with the benefits of a free flowing filter? correct if I’m wrong on any of this!
Isn’t David Vizard amazing?!
inim_repooc wrote:
How come no one makes a desent enclosed type filter/housing? Surely there’s enough minis of the newer type (spi/mpi) to make it worth while.
agreed! I think that the best thing to do for injection cars at the minute is to use the K&N filter that fits in the standard air box - these filters flow far better than standard filters, this is by having larger holes in the filter, but they have lots of little whiskers that catch the muck that gets through, similar to how nose hairs work! (ewww) this should manage to get any cooler air available into the engine and with the benefits of a free flowing filter? correct if I’m wrong on any of this!
Isn’t David Vizard amazing?!
Visard is amazing 
- but he did recommend cone filters… :shy: :lol:
