[johnung]

I'm considering aftermarket intakes that utilize the bottom of the stock N55 airbox. My reasoning is that I already have the bottom of the M Performance Intake which has more airflow than many aftermarket intakes. Often they just copy their intake hole size and shape from the stock BMW intake airbox.

I already know that the Dinan intake uses the bottom of the N55 stock intake airbox. Anyone know of any other aftermarket intakes with this feature that I should consider?

My goal for an aftermarket intake isn't more noise but rather the larger, smoother air tube to mate with the Pure Turbos Intake Pipe that's already installed. I'm just fine tuning the airflow path. Plus gotta admit that the Dinan carbon fiber looks great too! Engine bay bling!

[paul223]

K&N cold air intake

[indyjoeshmo]

The BMS intake uses the stock lower portion of the box.

[Fuel-It!]

The BMS intake retains the factory bottom.

[McQueen2014]

Originally Posted by Fuel-It!

The BMS intake retains the factory bottom.

Pretty sure that is for an e9x N55 and OP has an F30 N55 with the intake in the front.

[1QuikWS6]

Go with the Dinan that's what I use

I think there's one fs right now for good price

[AmuroRay]

Dinan. I’m about to swap back to my stock lower box though.

[johnung]

Originally Posted by 1QuikWS6

Go with the Dinan that's what I use

I think there's one fs right now for good price

Thanks! Saw that Dinan intake for sale too but we are on opposite coasts and he requires swapping with a stock intake, so 2X shipping to the other coast starts making it less attractive than me just buying a new Dinan Intake on-sale.

Here's a curious question for you since you own a Dinan intake...

I read through the Dinan intake installation instructions. Saw that they add a gasket between the existing bottom of the box, and the new Dinan top of the box. This essentially replaces the thick foam gasket that's a built-on part of the stock airfilter or any drop-in filter.

What if I don't install the Dinan gasket and instead leave in my aFe drop-in filter? Could I then install the Dinan top without its round cone filter? I can't quite see from photos how the Dinan top, the airfilter and the Dinan carbon filter tube all connect to know how feasible it is to just leave off the Dinan cone airfilter?

A couple of things occur to me on this...

Remember that my airbox bottom is not stock. I have the bottom from the M Performance Intake so it has much more air flowing up.

I wonder which has more filter surface area, the rectangular stock airfilter shape or the round Dinan airfilter if you were to split the cone out flat and measure the surface area in inches?

I also wonder what the flow efficiency is between the shape and material used in the aFe Pro Dry filter, and the material in the Dinan cone filter? Anyone know who really makes the filter for Dinan? and what material it is?

I also wonder what the sound difference may or may not be in my scenario of using either the flat aFe filter or the Dinan cone filter inside the same Dinan intake.

Any thoughts are appreciated.
HaHa, my brain has way too much time on its hands!

[johnung]

Originally Posted by AmuroRay

Dinan. I’m about to swap back to my stock lower box though.

Why?

[Logicoeur]

Originally Posted by johnung

Thanks! Saw that Dinan intake for sale too but we are on opposite coasts and he requires swapping with a stock intake, so 2X shipping to the other coast starts making it less attractive than me just buying a new Dinan Intake on-sale.

Here's a curious question for you since you own a Dinan intake...

I read through the Dinan intake installation instructions. Saw that they add a gasket between the existing bottom of the box, and the new Dinan top of the box. This essentially replaces the thick foam gasket that's a built-on part of the stock airfilter or any drop-in filter.

What if I don't install the Dinan gasket and instead leave in my aFe drop-in filter? Could I then install the Dinan top without its round cone filter? I can't quite see from photos how the Dinan top, the airfilter and the Dinan carbon filter tube all connect to know how feasible it is to just leave off the Dinan cone airfilter?

A couple of things occur to me on this...

Remember that my airbox bottom is not stock. I have the bottom from the M Performance Intake so it has much more air flowing up.

I wonder which has more filter surface area, the rectangular stock airfilter shape or the round Dinan airfilter if you were to split the cone out flat and measure the surface area in inches?

I also wonder what the flow efficiency is between the shape and material used in the aFe Pro Dry filter, and the material in the Dinan cone filter? Anyone know who really makes the filter for Dinan? and what material it is?

I also wonder what the sound difference may or may not be in my scenario of using either the flat aFe filter or the Dinan cone filter inside the same Dinan intake.

Any thoughts are appreciated.
HaHa, my brain has way too much time on its hands!

The drop in filter would need to be the same thickness/height as the dinan gasket. The clips on the lower box are fixed length.

[1QuikWS6]

Interesting idea using a flat element in the Dinan. It may be possible as the flange is present on the Dinan top cover, but you would need to actually test fit to make sure.

There definitely would be room without the round filter element. HOWEVER, due to the construction of the Dinan upper cover & position of the air inlet that element is attached to - you may find that the flat filter falls halfway in the opening leading to the turbo = unfiltered air would bypass the element and go directly to turbo

-or-

the round stub Dinan element attaches to inside the cover may interfere with flat element entirely. Only way to know would be to try

The top cover clips that were mentioned in post above are specific to the Dinan kit & new clips come with the kit to replace your originals

Now you would have (2) different clips to try out, mebbe one of them would yield correct clamping?

I would note that typically, a cylindrical element has more filtration surface area than that of a flat style. Of course that all depends on the round vs. flat overall size. I would need to have all the dimensions & run the calculations, but that is normally the case...

Dinan chose to use a cylindrical element for a reason - they could have much more easily designed it for oem flat style.

If you no like the oiled version element they sell, you may be able to find a dry style that fits.

I have never had a problem with oil on my sensors from the Dinan element. I do make it a habit of cleaning my MAF sensor with CRC every oil change just for preventative maintenance. But would not clean/re-oil the element myself. Once at the end of it's lifecycle I would simply buy a new pre-oiled element from Dinan

[1QuikWS6]

Note:

I thought about using the bottom MPerf intake with the extra red rimmed inlet hole - but then thought 2X about it & stayed with the closed version.

I didn't like the idea of sucking in hot underhood air while being in stop n go traffic.

I also use the Pure Turbo cast aluminum (opt 2) turbo inlet coming off the Dinan CF tube. It has more ID area than the OEM plastic part and the end @ the turbo does not have the pinched in diameter as the stocker = higher flow capabilities.

Whether or not this yields any noticeable HP is up for debate, but I have never seen a problem on my logs or dyno's with the Stg2 turbo that would relate to it being starved for air...

[Fuel-It!]

Originally Posted by McQueen2014

Pretty sure that is for an e9x N55 and OP has an F30 N55 with the intake in the front.

Good point. The BMS F30 intake is the same though retaining the factory airbox bottom for ducting!

[johnung]

Originally Posted by 1QuikWS6

Interesting idea using a flat element in the Dinan. It may be possible as the flange is present on the Dinan top cover, but you would need to actually test fit to make sure.

There definitely would be room without the round filter element. HOWEVER, due to the construction of the Dinan upper cover & position of the air inlet that element is attached to - you may find that the flat filter falls halfway in the opening leading to the turbo = unfiltered air would bypass the element and go directly to turbo

-or-

the round stub Dinan element attaches to inside the cover may interfere with flat element entirely. Only way to know would be to try

The top cover clips that were mentioned in post above are specific to the Dinan kit & new clips come with the kit to replace your originals

Now you would have (2) different clips to try out, mebbe one of them would yield correct clamping?

I would note that typically, a cylindrical element has more filtration surface area than that of a flat style. Of course that all depends on the round vs. flat overall size. I would need to have all the dimensions & run the calculations, but that is normally the case...

Dinan chose to use a cylindrical element for a reason - they could have much more easily designed it for oem flat style.

If you no like the oiled version element they sell, you may be able to find a dry style that fits.

I have never had a problem with oil on my sensors from the Dinan element. I do make it a habit of cleaning my MAF sensor with CRC every oil change just for preventative maintenance. But would not clean/re-oil the element myself. Once at the end of it's lifecycle I would simply buy a new pre-oiled element from Dinan

Thanks for the input. In researching I noticed that aFe makes a variety of cone filters with several types of elements. Both oiled and not oiled. Also aFe makes custom filters.

Makes me wonder who makes Dinan filters for them? And if aFe has one that would fit? If I buy a Dinan Intake I'll be sure to try out some scenarios and take measurements.

[johnung]

Originally Posted by 1QuikWS6

Note:

I thought about using the bottom MPerf intake with the extra red rimmed inlet hole - but then thought 2X about it & stayed with the closed version.

I didn't like the idea of sucking in hot underhood air while being in stop n go traffic.

I also use the Pure Turbo cast aluminum (opt 2) turbo inlet coming off the Dinan CF tube. It has more ID area than the OEM plastic part and the end @ the turbo does not have the pinched in diameter as the stocker = higher flow capabilities.

Whether or not this yields any noticeable HP is up for debate, but I have never seen a problem on my logs or dyno's with the Stg2 turbo that would relate to it being starved for air...

The pinched stock inlet is shown in attached photo. The Pure Turbos Inlet doesn't have that pinch and increases available air volume by 42% over stock plastic pipe.

Several guys including myself upgraded to the Pure Turbos Inlet while keeping the stock turbo. While not having a dyno available, we all saw consistent increases in our MAF values starting at 5000 RPMs. My understanding is the MAF value correlates directly to horsepower. We all felt an increase in power.