E21 M10 Cold Air Intake

[sw3457]

Hi -- I have a beautiful '81 320i, just had the upper half of the engine done. Now I'm hoping for a few extra horsepower and MPG, so I'm wondering if anyone knows where to find a compatible cold air intake system? I don't really want to move the battery to the trunk if I can help it. Maybe just get a filter upgrade? Thanks for any thoughts!
Scott

[JDTable]

Can't speak for the product since I've never used it, but Top-End Performance (TEP) has one available on their website for our cars:

https://www.racetep.com/automaker/bm...nlet-pipe.html


-edit: something to note is that the TEP product requires relocation of the battery

Also found Korman autoworks also offers a kit, but it also requires battery relocation:

http://www.kormanautoworks.com/e21.htm



I would be interested in anybody's experience with this or any other cold air intake



- Juan

[Ricochet Rabbit]

You can hope to see a few extra horsepower but probably won't see any except for maybe at really high RPMs. How much time to you spend at or near the redline? As to an increase in fuel economy, you can buy a lot of gas for the money you'll spend on a CAI.

[amarino]

Shouldn't the CAI be boxed up? I don't think having it open in the engine bay would help with getting cold air.

But I do have one of the Top End intakes that I bought second hand. I don't track my milage or have a dyno from before or after. The only thing I do notice is you can hear the intake sucking noise, so that's cool.

[sw3457]

Shouldn't the CAI be boxed up? I don't think having it open in the engine bay would help with getting cold air.

But I do have one of the Top End intakes that I bought second hand. I don't track my milage or have a dyno from before or after. The only thing I do notice is you can hear the intake sucking noise, so that's cool.

Which one did you get?

[amarino]

Which one did you get?

The Top End Performance one mentioned above. I bought it used off the forums years ago https://www.racetep.com/automaker/bm...nlet-pipe.html

[SoCalE21]

That looks like a hot air intake.

[charter21p5]

I use k&n filters in my BMWs. They open up the airway.


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[Bonsaibacker]

I’m curious in this conversation cause I think that section of the engine bay is terribly congested. I have moved my battery to the trunk and want to do an alternative intake just to improve the aesthetics and visibility. The need to remove the air box to view anything has challenged me since day one.


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[m60b30530i]

https://www.racetep.com/automaker/bm...-efi-kits.html

[charter21p5]

https://shop.advanceautoparts.com/p/...E&gclsrc=aw.ds


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[OLD MAN]

I have one I designed years ago and was thinking of putting into production - but just was not sure I could sell enough to make it worth while to invest in.

Open air intake inside the engine bay is not a cold air intake - for a true cold air intake all the air needs to come from outside the engine bay. By either a closed off hood scoop or from in front of the radiator core support.

Cold air intakes can make more HP because cold air is denser then heat air.

[OLD MAN]

There is another way to do a simple DIY cold air intake using the stock 80-83 air box.

Cut the intake tube off the lid of the box and mount it to the front side of the lid - plug the hole made from cutting the tube off the face of lid.

Remove the driver side front high beam and connect a flexible tube from the air box tube to the back of the light mount. I put aluminum window screen in place of the high beam as a filter. See sig picture below.

- - - Updated - - -

NOTE battery needs to be relocated to trunk for better tube fitment.

[duuder]

Do you have pics of your old set up?

[OLD MAN]

this one
Coldairintake 3.jpg

[jaredmac11]

It looks like it in the picture you have in your signature, but Im assuming you removed the headlight for airflow?

[OLD MAN]

It looks like it in the picture you have in your signature, but Im assuming you removed the headlight for airflow?

I had to remove the head light to make room for the filter - plans are to revise the box so the filter can be moved back behind the head light.

But yes with the head light out more air can flow in for the higher RPM I drive at.

[jaredmac11]

Right now, my M42 is using the stock airbox, I would like to pipe it behind that light but I wasnt sure just how much airflow it would get. I think you have the right setup for a truly cold air, cold air intake.

[OLD MAN]

Right now, my M42 is using the stock airbox, I would like to pipe it behind that light but I wasnt sure just how much airflow it would get. I think you have the right setup for a truly cold air, cold air intake.

Thanks - I am still thinking about making these for sale, just not sure what they will cost.