Air Intake Mod... Moving To Cold Air Intake...
 

When I bought the car it already had the air intake mod done (picture) however while I can understand this works better than stock... it's still an awful awful design, as your not funnelling air at all.

So that brings me to the next step up, fitting an intake from the air-box into the bumper - which seems a lot better.

I'm just very nervous about what I might suck up now the air intake can actually suck anything up - for example this thread warns of water being sucked in, but does standing water ever really get that high? and is there any way to reduce the risk of stuff getting sucked up?

I'm in the exact same situation with the same worries.

After driving through some torrential rain a few weeks ago, I don't feel comfortable putting a cold air feed to the cutout beside the fogs/under the indicators as I can see water ingress easily happening there - and I can't think of anywhere else to put it(except to mod the bonnet to put in a reverse snout, but that's an awful lot of work and a lot of money).

Firstly it isn't just standing water you need worry about. On a diesel the compression ratio is almost double that of a petrol engine, i. e. its around 18 to one on a diesel. That makes for a very small combustion chamber. so just how much, or rather how little, road spray/splash will it take to cause a hydraulic lock up on an m47r engine???? :o :shrug:

In my opinion it is far too risky to put an unrestricted air intake very low down on the front of your car! :o :confused: :confused:

Another point, taken from the photos of the mod done on the link given, is that that particular car has no fuel burning heater fitted, were there to be one, the air pipe would be too large to fit into the remaining space.. :shrug:

It would be feasible to drill small holes in the forward facing sections of the concertinaed part of the original air intake to allow more air to enter that way. But how effective that would be is a moot point. it would also be dependant on the size, number, and location of said holes.. :shrug:
...

Been doing some more thinking - first of all the point to remember is that the original air intake was designed to feed a 115 BHP engine, with a more relaxed Rover 75 driver at the helm... it works with 135 BHP, but as a lot of owners are now at 150+ BHP with simple bolt-on mods it just isn't really good enough.

There are 3 ways to do this.

1 - Run something from the very small front intake to the air intake whole near the airbox. Ideally using some low-resistance tubing. You will need to butcher / remove the engine cover a lot, but this is safe from water, cold air and better than OEM... but not by a massive amount as the actual air intake is still woefully small.

2 - Run a pipe from the airbox to the blocked off vent near the foglight. Lots of air, nice and cold as well, however it's only possible on the passenger side which isn't ideal as thats where puddles / NAUGHTY WORD-NAUGHTY WORD-NAUGHTY WORD-NAUGHTY WORD- builds up thanks to the crown of the road. You can get special filters to put over the intake to reduce water intake, but MAF deterioration and even hydro lock is a serious risk.

3 - Carl's solution. Run a pipe from the blocked off vent, ending where the edge of the bellows used to be. This gives cold air, but not a huge amount will be sucked up. If you combine this with with the air intake mk2, the forward motion of the car will force some air in the vent, up the tube to the area *near* the air intake. Theres little active suction, so the risk of water / debris coming up is low and even if it does it's unlikely to get sucked up the intake instead of just falling back down. I think this would be the best, however i'm not sure how much suction power the engine actually generates, and how much air will be forced in via the act of driving along. The advantage of this is that you retain all the peformance and reliability of the mk2 air intake mod, but you get a *bit* more air.

Alas, the last person who took my bumper off rounded off most of the screws so I can't really investigate myself :(

Bump...

What about the solution on pmessling's 260?

http://i100.photobucket.com/albums/m...g/e10d6b62.jpg

And how much BHP difference is better breathing going to make?

AEM make a nice connector that effectively eliminates the chance of hydrolocking with a long arm cold air intake.. Look for an AEM V2 and you'll see the filter fits down into the bumper as per the picture above, a pipe then runs into the engine bay, where it connects to another pipe leading to the intake manifold via a small breathable connector.. Should the filter in the bumper become submerged in standing water, your engine breathes through the breather in the engine bay. Simples. The V2 is about £200, but you can buy the breather on it's own for around £40 - I have the exact set-up on my Honda.

I remember reading up about this, and AEM saying you could only use the breather with their air intake (but then they would say that).

The real question is, how much extra performance am I going to get to make it worth it...

5BHP tops, but the noise of the things is phenomenal.. Plus, breathing mods always feel like they add more than they actually do..

"noise of the thing"? It's a diesel fgs :p

Induction roar is nice! If someone finds a breather and mods their CTDi with it, I'd love to see it.