[WD335D]

Hi everybody, looking at doing the swirl flap delete but cant seem to find an answer on what size block plates to buy. Can anybody help?

there seems to be two sizes 33mm
https://www.ebay.ca/itm/6Pcs-33mm-Di...d/231986907519

and 22mm

my engine is the the M57y
on a 335d

[335dlci]

Aarod sells them

[CMichael]

My us market x5d used the 33mm version

[BB_cuda]

33 mm

[335stoner]

i just bought 33mm for my car and i will be installing deletes on a customers car next weekend. he bought Arods kit and i will compare the two sets.

[Mussof]

+1 on AARod. I got mine from there.

Swirl Flap Delete Kit - BMW 335D and X5 35D (AAR2136)

[Pep423]

Originally Posted by Mussof

+1 on AARod. I got mine from there.

Swirl Flap Delete Kit - BMW 335D and X5 35D (AAR2136)

Same

[bmwdiesel]

i requested to put them back on after higher fuel and lower power.....some dont feel it, i am sure i did. also there are there for a reason to swirl the air/combustion....how the engine works? fuel plus air......more air more power, u do the math

[Nadir Point]

Originally Posted by bmwdiesel

...also there are there for a reason to swirl the air/combustion...

Yeah, it's interesting to me from a human nature perspective, how you see guys in these car forums (this is just 1 of MANY examples) with little to no real engineering or scientific experience, look at something and imagine why they need to change/mod/delete it with absolutely no understanding of what they are doing.

https://www.e90post.com/forums/showp...6&postcount=13

[335stoner]

the better question is

do the flaps even function after a computer tune?

[M5_1of400]

Originally Posted by Nadir Point

Yeah, it's interesting to me from a human nature perspective, how you see guys in these car forums (this is just 1 of MANY examples) with little to no real engineering or scientific experience, look at something and imagine why they need to change/mod/delete it with absolutely no understanding of what they are doing.

https://www.e90post.com/forums/showp...6&postcount=13

Pretty sure plenty of people read and understood the "engineering" reason and saw no value in it..

[Nadir Point]

Originally Posted by DieselDemonDM

Pretty sure plenty of people read and understood the "engineering" reason and saw no value in it..

That's what happens when people who don't know what they are doing pretend to be engineers.

[CMichael]

My desire to delete the swirl flaps on my 2010 x5d came from a survival standpoint; several swirl flap screws were loose and ready to fall out. I understand the engineering value but I'll take the safety of my engine over a slght boost in off idle torque.

[Owen81]

It says right in the functional description that they were implemented for low engine speed emissions with "otherwise no effects" if they are stuck open.

All I know is that mine were leaking boost and getting oil all over the components underneath the intake manifold. Since I have removed all other emission control devices that were engineered for my car, there is no reason to keep them.

[Nadir Point]

I'll continue holding off engineering decisions based on publicly available tech info. And if the screws fall out and trash the engine, I'll rebuild it to stock spec and try again.

[335stoner]

The screws falling out was an EU engine issue not a NA issue. i think that because it is on the internet that most people think it applies to all the m57 motors.

i will be changing my SF for blanks soon ONLY real reason is i want to see if it makes any difference in fuel economy. i calculate my MGP by fuel pumped to miles driven (not the dash) my real MPG average about 34.5. if it goes down or i see a decrease in performance ill pull the intake and swap them back out it will only take about an hour to pull and swap back..

[335stoner]

FWIW

i got to do an almost side by side comparison of Arods swirl flaps VS ebay or amazon swirl flaps. i noted down some good mental notes on my amazon kit..

the only real difference i could truly note was exterior finish. the $20 amazon has more circular machine marks on the exterior finish. it was still done on a CNC it was just had no post finish to the exterior. the seal surfaces looked the same (shiny and smooth) and the size and weights seemed to similar. the O-rings both seem to be the same cheap soft black O-ring with a noticeable seam line on the outside. i might swap mine out for some higher quality 70-90 durometer viton O-rings...

if i have any fitment issues ill post back, but given the simple design i highly doubt ill have any.

[CMichael]

Originally Posted by 335stoner

The screws falling out was an EU engine issue not a NA issue. i think that because it is on the internet that most people think it applies to all the m57 motors.

I can assure you that this issue also applies to NA M57 models. On my 2010 x5d multiple swirl flaps had screws that were halfway unscrewed and could easily be rotated by hand. This was at 189kmi, and seen with my own eyes. I had originally planned to keep the flaps after my intake manifold cleaning, but seeing how close my engine was to ingesting a screw made me decide to install blanks instead.

[Nadir Point]

My bet is on a fuel mileage drop and corresponding loss of low-end torque. Maybe not real noticeable, but you can be sure it's there. Run it by one of those roadside emissions checkpoints and you'll see an increase on that - just like BMW claims.

But seriously - don't get caught driving a deleted 335D!

[335stoner]

I'm not one to really care about the emissions side of it..

one question i have about the tunes is do the flaps even function after a tune? ** if they get tuned out and don't function (stay open)**

[Nadir Point]

Originally Posted by 335stoner

I'm not one to really care about the emissions side of it..

one question i have about the tunes is do the flaps even function after a tune? ** if they get tuned out and don't function (stay open)**

I cannot imagine why a tuner would go there. But that is a question for them. I can see it coded out if they are not there any more, but why do that if they are still there?

[335stoner]

Originally Posted by Nadir Point

I cannot imagine why a tuner would go there. But that is a question for them. I can see it coded out if they are not there any more, but why do that if they are still there?

i also would see no reason to function code them out. only ses code out for those who want them out... my gut says they still work, but sometimes my gut gives me diarrhea