Bmc Cda

[GandalfS6]

I bought my S2 with a large BMC cone filter installed and I don't have the original airbox.

The problem is that South Africa can get pretty hot and add to that the the Cone Air Filter sits right on next to the turbo, the car is just sucking in hot air. This kills performance but even worse so on a hot day (more than 30 degree C). I have been thinking that I should buy a RS2 airbox but they cost GBP 177 and then I would still have to buy a performance air filter.

I recently saw the BMC CDA (Carbon Dynamic Airfilter) on the internet (see http://www.bmcairfilters.co.uk/infoCDA.asp). It looks to me like an interesting concept - the filter is encased in carbon fibre which keeps the heat away from the air and is supplied with alloy ducting which can be placed somewhere where cold air enters the car. The filter is also shaped to produce a ram air effect.

This is technology used in racing and according to BMC gives significant performance increases . They dynoed a RS4 (http://www.fabspeed.com/bmc%20dyno.htm) and it shows an increase of 11 HP and 43 Nm (at 700 less rpm!). It costs around GBP145 which is much cheaper than a RS2 airbox and performance filter.

Below is a picture of a CDA installation on a TT.

Has anybody had any experiences with a CDA? To me it looks like the perfect solution!

[GandalfS6]

Oops forgot to attach the picture! It looks quite

[Mark Halligan]

I have been thinking about using one of these too for a while, as my filter is down very low, good for clean cold air but I am also running the risk of sucking up a puddle if I dont do something about it soon, and I'd hate to hydrolock my new engine once I get it in. One nice thing about these is they come made ready to accept the MAF which fits into one end of it.

I'd also be interested to hear of anyones experiences with one of these.

Cheers,

Mark.

[Sweeper]

There are also a Pipercross Viper sieries with a very good results on test. And they manufactured in England(?).

Altrought expensive.

There should be a way to prevent sucking a puddle , which I doubtly know

Any suggestions from engineers ? (Marco?)

[Pisobiker]

Hmmm.... I think best way to prevent this happening is placing the inlet tubing higher, over the front bumper.
Alternatively might be possible to build a box nicely fed with fresh air through an "air scoope", but having a couple of internal dividers that could allow water to drain out before being sucked by the inlet pipe.
This, anyway, looks like a sort of airbox to me (which Audi has already provided for ), so why just not finding the way to feed fresh air from over the bumper trying also to improve inlet of ducting to benefit from a small amount of dynamic supercharging? Might be possible to fit a well shaped inlet just behind left side of front grille.....


Marco

[Mark Halligan]

This is why I am scared of deep puddles, I've never spent so much time watching the weather , mind you though, good for cold intake air, and sounds great too.

[Craig]

Cone filter

Hi Gandalf

If I remember correctly, Gerald?, the guy in Cape Town who sold his RS2 recently had the same heat problem. He also replaced his filter box with a cone so he may be able to help. I think he might have gone back to back to his oem box though. Can't recall.

Regards
Craig

[Stick Insect]

Mark, et al you don't need that deep a puddle to hydrolock the engine, Sarah went through a flooded road junction in her Citroen ZX diesel the water was 3 inches ( 75mm) and it caused a bow wave which was sucked up. She ended up next to a Peugeot which had done the same!

Auxiliary radiator out of the way and have a cold air scoop behind?

Carlos Sainz style bonnet scoop anyone?

D.

[Mark Halligan]

Mark, et al you don't need that deep a puddle to hydrolock the engine

Yep I know, thats why I have got to change it. It was done in a rush when I was fitting the mods last summer and it took me two days and lots of wasted SFS tubing trying various different ideas, it was a compromise. I know Dahlback put it in 'roughly' the same place but I am far from happy about its location and it has to move before I get the new engine in. I was thinking that I could mount the CDA box there and then route the inlet tubing up higher nearer the bonnet grill and this should be ok as the CDA box is sealed and water splash/immersion wont matter?

Cheers,

Mark.

[s2avant]

I'll be ordering a BMC CDA in a few weeks when my RS2 MAF arrives. RS2 airbox's are now silly money so I'm going to take this route instead.

I know a lad that works for Graham Goode and he has one on his Integra. He says he can feel a difference in the performance although maybe not how much they claim.

He's pricing it up for me this week.

Ben

[dan_b]

Mark - how many pedestrians have you sucked in to the intake with it there?!!

I can totally understand your fear of water ingestion though - but just a thought, with that location, aren't you also going to suffer from heat soak from the brakes, and possibly ingesting brake dust?

Hang on, you probably run with the bumper on don't you, whoops

I'll go back in to my cave...