Stock intake and front grill question - The Unofficial BMW M5 Messageboard (m5board.com)

sublimaze · 6th April 2005, 18:39

Where does the stock intake get its' air from? I've looked under the car, but I don't see any openings. I saw a channel in the front wheel well, but I think that directs air to the brakes.

Also, why does the front grill have only have holes in solid part of the drivers side and not the passengers' side?

Thanks

kcdoyle · 6th April 2005, 18:48

Quote:

Originally Posted by sublimaze

I saw a channel in the front wheel well, but I think that directs air to the brakes.

Also, why does the front grill have only have holes in solid part of the drivers side and not the passengers' side?

Thanks

sublimaze-

Sounds like someone started to put the brake air ducts on the car but only got to one side.

Ahmed · 6th April 2005, 18:57

The stock air intakes are exactly behind the front bumper, you cannot see them from the outside!

The holes on the grill have no relevance except for making their removal easier by using your fingers!!! Thats all!

sublimaze · 6th April 2005, 19:11

Quote:

Originally Posted by kcdoyle

sublimaze-

Sounds like someone started to put the brake air ducts on the car but only got to one side.

I don't think that's the case, the car is completely stock( for now) and CPO'd when I bought her.

sublimaze · 6th April 2005, 19:25

[quote=Ahmed]The stock air intakes are exactly behind the front bumper, you cannot see them from the outside!

Again, so how does the air get in behind the bumper? Could I just drill some holes through the fog light cover to increase airflow?

I've read other posts where people, Elevens and NAVYBO come to mind, have made a DIY CAI by removing the fog light covers and replacing them with mesh to allow more air to flow through. But then they also had to cut part of the stock air intake hose. That's the part I did not understand. Can't you just make the openings and forget about it?

mottati · 6th April 2005, 19:53

with the hood open, try to look below the headlamps, and you should see the air intakes. Opening the foglamp surrounds will do nothing with the intakes in the stock position, too far away. You would have to cut or remove the intake snorkles from the airbox. I had my snorkles off and open foglamp surrounds for a while. It should allow more air when the car is at speed, but hard to feel any difference. in theory, this would make the front fenderwell area (behind the foglamps) a large air plenum, that could see some positive air pressure at high speeds, which would feed into the stock airboxes.
Mike

Quote:

Originally Posted by sublimaze

Again, so how does the air get in behind the bumper? Could I just drill some holes through the fog light cover to increase airflow?

I've read other posts where people, Elevens and NAVYBO come to mind, have made a DIY CAI by removing the fog light covers and replacing them with mesh to allow more air to flow through. But then they also had to cut part of the stock air intake hose. That's the part I did not understand. Can't you just make the openings and forget about it?

gilmores m5 · 6th April 2005, 20:46

i've looked into this as well. seems like you can connect a flex hose from the stock air intakes to the either the front grill or the bottom grill providing it is protected from water.also looked at drilling holes in the plastic front grill and connecting a flex hose to the brake system in the wheel well.but all this sounds good in theory but will it do any good.

??

Hector Lopez · 6th April 2005, 21:20

How much more air, realistically, can you get through the air filters?

mottati · 6th April 2005, 21:21

Quote:

Originally Posted by gilmores m5

i've looked into this as well. seems like you can connect a flex hose from the stock air intakes to the either the front grill or the bottom grill providing it is protected from water.also looked at drilling holes in the plastic front grill and connecting a flex hose to the brake system in the wheel well.but all this sounds good in theory but will it do any good.

??

The people at actve autowerks feel it's worth 25hp! Hard to believe, but there's been good feedback on their system.

As a side note, your don't really need to worry too much about water ingestion, the stock airboxe, i believe the passenger side (for US spec car) has an extra intake pipe that goes into the top of the fenderwell area to avoid water ingestion.
Mike

jaj · 7th April 2005, 09:09

When I put my brake ducts in I took a long hard look at the way that air gets into the engine. The two main snorkels open into the enclosed space behind the front bumper. On the right side (looking from the driver's position and facing forward), there's a second branch to the snorkel that goes to an opening in the fender well, presumably to fetch cold air from there. On the left side, the row of holes at the top of the lower grill provides what appears to be the only cold-air inlet to the space where the snorkel is.

That's it - there's no magic and no access from the snorkels to the outside air, except for that little row of holes on the left side. Of course the space is not sealed, although it is baffled, so apparently enough air gets in there to make 400 horsepower. At speed of course, that row of half-inch holes lets lots of cold air in, I'm sure.

When I installed my factory M-Sport grill insert (with the splitter) I drilled a row of holes across the top of both brake duct tubes (left and right) to fulfil the function of the lost holes in the stock grill insert. I'm not sure that breathing would be inhibited without the row of holes, but it's the only source of outside air for the intake snorkels.

Cheers
JJ