aero tech- wings, lips, diffusers, canards, etc.

[Greg S]

Originally Posted by jakob66

Hey Greg!
Aluminum.
Are you racing TT3 at Watkins Glen?
Any updates from your racer?

Yes. Started working on it again this past week, but probably won't post much about it until after Watkins... because sneaky.

[ThunderMoose]

Originally Posted by jakob66

Hey Greg!
Aluminum.
Are you racing TT3 at Watkins Glen?
Any updates from your racer?

Will you be at WGI?

[jakob66]

Originally Posted by ThunderMoose

Will you be at WGI?

Yes, will be my 1st time up there. Exciting!

[Richbot]

Oh man, WGI with real downforce will be a good time

[ThunderMoose]

Originally Posted by jakob66

Yes, will be my 1st time up there. Exciting!

I'll be there too in my E46M3.

[shad0wfax]

Do we have any updates here?


For those who have enough track experience:

Of all of the cosmetic aero items and kits out there, which brands/models are actually beneficial on the track for the E92 M3?

I know that the right rear spoiler will reduce rear lift and turbulence (and slightly reduce top speed) and I know that the right wing will actually add rear down force (with a more marked impact on top speed reduction).

I know that the right rear diffuser will reduce rear lift and turbulence of air exiting under the car and even potentially increase top speed, but that this also is most beneficial if the car is very low and essentially flat underneath.

I know that the right front splitter will reduce front lift and further reduce turbulence under the car.

I'm also familiar with Gurney flaps and canards (aka dive planes).

Before anyone jumps the shark, I'm aware that apart from DTM and LM types, must of us will never see a wind tunnel or even run a CFD model on our cars, so I'm not looking for truly scientific details.

What I'm wondering is if anyone has subjective opinions or, better yet, empirical evidence from track times, with any of the more commonly available aftermarket products.

Form follows function for me, so I'm curious for more details from others.

[roastbeef]

Originally Posted by jakob66

Hey guys
Just want to give you a heads up on my diffuser system that I developed and built in the last couple of months. It goes all the way to the front axle. I installed rear travel transducer with display in dash so I can see what happens in the rear. I tested on public roads and it does generate downforce. I will report back after race this weekend.
I received plenty requests to make a built thread of my car but I have to apologize I just had no time. Maybe later in the year.
Cheers
Attachment 1478110
Attachment 1478111

we need more pictures of this beast.

[jakob66]

Originally Posted by roastbeef

we need more pictures of this beast.

It's coming...I will offer the diffuser along with my roll cage and other goodies that I developed for the TT racer shortly for sale.
The diffuser was the single best improvement to drop my lap times.
Stay tuned!
Thanks

[roastbeef]

Originally Posted by jakob66

It's coming...I will offer the diffuser along with my roll cage and other goodies that I developed for the TT racer shortly for sale.
The diffuser was the single best improvement to drop my lap times.
Stay tuned!
Thanks

We'll hit me up when it's available!

[jakob66]

Originally Posted by roastbeef

We'll hit me up when it's available!

Will do!

[roastbeef]

Originally Posted by shad0wfax

Do we have any updates here?


For those who have enough track experience:

Of all of the cosmetic aero items and kits out there, which brands/models are actually beneficial on the track for the E92 M3?

I know that the right rear spoiler will reduce rear lift and turbulence (and slightly reduce top speed) and I know that the right wing will actually add rear down force (with a more marked impact on top speed reduction).

I know that the right rear diffuser will reduce rear lift and turbulence of air exiting under the car and even potentially increase top speed, but that this also is most beneficial if the car is very low and essentially flat underneath.

I know that the right front splitter will reduce front lift and further reduce turbulence under the car.

I'm also familiar with Gurney flaps and canards (aka dive planes).

Before anyone jumps the shark, I'm aware that apart from DTM and LM types, must of us will never see a wind tunnel or even run a CFD model on our cars, so I'm not looking for truly scientific details.

What I'm wondering is if anyone has subjective opinions or, better yet, empirical evidence from track times, with any of the more commonly available aftermarket products.

Form follows function for me, so I'm curious for more details from others.

in all my reading, etc., us weekend guys are left to the grueling process of trial and error. the most scientific evidence we are going to get is someone with an AIM solo DL posting data before/after adding aero. dogbone has done this, but his car was evolving fast and it was at a time when his car was recently gutted.

i will be adding an apr splitter and a gts style wing soon. i'm pretty consistent at willow springs, although i don't have AIM solo data, i'm pretty in tune with the feel of the car and i feel that i will be able to give an unbiased opinion on adding minor aero.
i have been looking at adding a functional diffuser as well. i really like the aeroflow dynamics design.

[dogbone]

Originally Posted by shad0wfax

Do we have any updates here?


For those who have enough track experience:

Of all of the cosmetic aero items and kits out there, which brands/models are actually beneficial on the track for the E92 M3?

I know that the right rear spoiler will reduce rear lift and turbulence (and slightly reduce top speed) and I know that the right wing will actually add rear down force (with a more marked impact on top speed reduction).

I know that the right rear diffuser will reduce rear lift and turbulence of air exiting under the car and even potentially increase top speed, but that this also is most beneficial if the car is very low and essentially flat underneath.

I know that the right front splitter will reduce front lift and further reduce turbulence under the car.

I'm also familiar with Gurney flaps and canards (aka dive planes).

Before anyone jumps the shark, I'm aware that apart from DTM and LM types, must of us will never see a wind tunnel or even run a CFD model on our cars, so I'm not looking for truly scientific details.

What I'm wondering is if anyone has subjective opinions or, better yet, empirical evidence from track times, with any of the more commonly available aftermarket products.

Form follows function for me, so I'm curious for more details from others.

The short answer: From personal experience, you need aero on the back AND front. Buy a 67" APR trunk mounted wing, basic front lip with flat bottom, APR splitter and get that all mounted up. Bottom line: The results are universal---if you're driving at the vehicle's limit with no aero, the full aero setup will make the car 2-3 seconds faster at pretty much every track.

Buttonwillow: 1:54--->1:49 (The more fair comparison comparing MDM-on to MDM-on would be 1:54--->1:51)
Big Willow: 1:29--->1:27
Chuckwalla CW: 1:58--->1:55
Laguna Seca: 1:39--->1:36
Auto Club: (Previous to getting aero my time was REALLY slow at ACS because I don't go very often, but then I went with aero and as a better driver)--->1:46

A few days ago, I wrote about some of my thoughts regarding aero in this thread. I think these are the kinds of opinions you're looking for: (posts 24, 27, 30) http://www.m3post.com/forums/showthr...1338859&page=2

[roastbeef]

pretty cool aero thread in here from our 335 brethren. dude quantifies it with some data as well.

http://www.e90post.com/forums/showthread.php?t=629044

http://www.trueformtech.com/

[shad0wfax]

Originally Posted by roastbeef

in all my reading, etc., us weekend guys are left to the grueling process of trial and error. the most scientific evidence we are going to get is someone with an AIM solo DL posting data before/after adding aero. dogbone has done this, but his car was evolving fast and it was at a time when his car was recently gutted.

i will be adding an apr splitter and a gts style wing soon. i'm pretty consistent at willow springs, although i don't have AIM solo data, i'm pretty in tune with the feel of the car and i feel that i will be able to give an unbiased opinion on adding minor aero.
i have been looking at adding a functional diffuser as well. i really like the aeroflow dynamics design.

Thank you for the response. These sorts of subjective opinions still help me make my decisions. I was originally thinking about Fstreet, which would mean no aero, but my vehicle already has some carbon fiber front splitters (just the side ones, not an entire lip), and it has the M performance higher profile carbon fiber spoiler (or else an aftermarket lookalike). The spoiler is pretty functional, I believe. I'm pretty sure it would pass muster at local events, but if I ever got good enough for nationals, I couldn't do Fstreet without removing it, as the car was shipped with the spoiler delete option. So now I'm looking at crazy aero mods and just using Autocross to learn through self-improvement, and I don't really care where I'm classed or if I "win" or not. Thus, I'm thinking of building a mild streetable car that's nicer on the track. (Though I'll never go with a true track setup so long as I'm still using it on the street.)

Originally Posted by dogbone

The short answer: From personal experience, you need aero on the back AND front. Buy a 67" APR trunk mounted wing, basic front lip with flat bottom, APR splitter and get that all mounted up. Bottom line: The results are universal---if you're driving at the vehicle's limit with no aero, the full aero setup will make the car 2-3 seconds faster at pretty much every track.

Buttonwillow: 1:54--->1:49 (The more fair comparison comparing MDM-on to MDM-on would be 1:54--->1:51)
Big Willow: 1:29--->1:27
Chuckwalla CW: 1:58--->1:55
Laguna Seca: 1:39--->1:36
Auto Club: (Previous to getting aero my time was REALLY slow at ACS because I don't go very often, but then I went with aero and as a better driver)--->1:46

A few days ago, I wrote about some of my thoughts regarding aero in this thread. I think these are the kinds of opinions you're looking for: (posts 24, 27, 30) http://www.m3post.com/forums/showthr...1338859&page=2

Thank you for the response and recommendations. I'm wondering how feasible it is to make the car even flatter underneath, as I know that the smoother/flatter the entire undercarriage is, the better the front splitter and rear diffuser will work.

[roastbeef]

Originally Posted by shad0wfax

Thank you for the response and recommendations. I'm wondering how feasible it is to make the car even flatter underneath, as I know that the smoother/flatter the entire undercarriage is, the better the front splitter and rear diffuser will work.

you saw the link in my post #57, right? thats as flat as i think it could reasonably get.

[shad0wfax]

Originally Posted by roastbeef

you saw the link in my post #57, right? thats as flat as i think it could reasonably get.

I did, and from the angles that I can see, it looked pretty darned good. I also noticed the barriers at the outboard of the body to channel keep the higher speed (lower pressure) air under the chassis where it belongs.

[roastbeef]

thats pretty badass. probably the best way to get downforce and i don't think it causes much drag. i really like how a weekend guy like me could use something like this for improvement without sacrificing the appearance of the car with more extreme aero.

[shad0wfax]

Originally Posted by roastbeef

thats pretty badass. probably the best way to get downforce and i don't think it causes much drag. i really like how a weekend guy like me could use something like this for improvement without sacrificing the appearance of the car with more extreme aero.

I wonder what the distributed forces are on the parts and if ABS or Polyethylene HDPE are up to the job, or if sheet aluminum would be better.

I'll have to look into their stiffness vs density. (I can't afford to do custom carbon fiber molds for this.)

[roastbeef]

my friend and fab guy that built my truck and made me some mounting tabs for my apr splitter has worked with carbon fiber, kevlar, and balsa wood composites pretty extensively when building competition spec remote controlled planes. he is thinking we could build poster board prototypes, then buy the desired material and bond it together. i think the biggest challenge is that the bottom of the car isn't completely flat. all the little screws and crap holding that felt on are almost countersunk... so we'll have to make a small spacer sleeve over the bolts so the panel can screw on firmly without distorting the felt.
check out this website. raw materials aren't too expensive... its just time and effort.
http://www.acpsales.com/OnlineStore.php?cat=5361

[shad0wfax]

Originally Posted by roastbeef

my friend and fab guy that built my truck and made me some mounting tabs for my apr splitter has worked with carbon fiber, kevlar, and balsa wood composites pretty extensively when building competition spec remote controlled planes. he is thinking we could build poster board prototypes, then buy the desired material and bond it together. i think the biggest challenge is that the bottom of the car isn't completely flat. all the little screws and crap holding that felt on are almost countersunk... so we'll have to make a small spacer sleeve over the bolts so the panel can screw on firmly without distorting the felt.
check out this website. raw materials aren't too expensive... its just time and effort.
http://www.acpsales.com/OnlineStore.php?cat=5361

Raw carbon fiber weave is inexpensive, as are the resins. The real artistry in getting light, stiff, and consistently formed carbon fiber is in the strand orientation, the resin used, the heat applied, and how good of a vacuum mold or weight mold you have.

I'm wondering if some thin aluminum would be easier to fabricate; I doubt that there would be much of a weight penalty compared to carbon fiber. Ideally, we'd be replacing all of the felt items and using existing fastener locations. Some aluminum pillars/sleeves/shims would allow for leveling.

[roastbeef]

Originally Posted by shad0wfax

Raw carbon fiber weave is inexpensive, as are the resins. The real artistry in getting light, stiff, and consistently formed carbon fiber is in the strand orientation, the resin used, the heat applied, and how good of a vacuum mold or weight mold you have.

I'm wondering if some thin aluminum would be easier to fabricate; I doubt that there would be much of a weight penalty compared to carbon fiber. Ideally, we'd be replacing all of the felt items and using existing fastener locations. Some aluminum pillars/sleeves/shims would allow for leveling.

I have been told the felt has a component to it that guards against outside electrical interference, unless I misinterpreted what was told to me. I'm just not sure if I want to mess with it.

[dogbone]

Originally Posted by shad0wfax

Thank you for the response and recommendations. I'm wondering how feasible it is to make the car even flatter underneath, as I know that the smoother/flatter the entire undercarriage is, the better the front splitter and rear diffuser will work.

I've never seen an E9x M3 with a full flat bottom. I believe the common goal is to have the splitter smooth out the underside to around the front axle. The APR is a pretty big piece and basically does that.