E30 Aerodynamics

[BlackbirdM3]

Vortex generators are interesting and highly effective in some applications. You don't need big pieces of molded plastic to have a vortex generator, the ones you see on aircraft are mostly little pieces of bent aluminum installed at an angle with respect to air flow. They don't have to be very tall, since they only act to keep the boundary layer attached, I've seldom seen them more than 1.5" in height on private and small commercial aircraft. I have even seen them put on RC planes and have seen a noticeable difference in stall characteristics. When you look at the roofline of an E30 from the side, you can tell that there will be serious flow detachment on the rear window because of how steep it is. An A/B tuft test is simple, and some small vortex generators placed along the roofline in a manner similar to what you see on an old Mitsubishi Evo would most likely make a noticeable difference in air flow over the rear window. How much of a difference this would make on the track or for fuel economy would have to be seen. I suspect not much.

I've thought about putting them on my E30 before, just never got around to it, finding some cheap ones or fabricating my own.

The step above the rear window on an M3 does this same thing. They spent a lot of time in the wind tunnel working out the best setup.

Will

[2mAn]

Simon, how much did you pay for your airtabs? I've sold a couple of sets of my 3d printed VGs at $35 shipped for 8, and you get a credit for the injection molded product when it's finished with manufacturing

Mine cost about the same , and like I said if I knew you were going to start producing them I would rather support a forum member than some random person.

The step above the rear window on an M3 does this same thing. They spent a lot of time in the wind tunnel working out the best setup.



Will

I've looked into adding that c-pillar as I'd get the benefit of the air turbulence and, more importantly, the angle of the rear window, but it's a NLA part now

Wish I had an M3 lol

[squidmaster]

oh no dude that's not why I asked. I was just curious how to price mine competetively

[2mAn]

oh no dude that's not why I asked. I was just curious how to price mine competetively

Yours are priced right, I meant nothing by my comments except that I'd prefer to keep the money here rather than outside sources

[BlackbirdM3]

Mine cost about the same , and like I said if I knew you were going to start producing them I would rather support a forum member than some random person.





I've looked into adding that c-pillar as I'd get the benefit of the air turbulence and, more importantly, the angle of the rear window, but it's a NLA part now

Wish I had an M3 lol

There is a guy making full carbon fiber rear window assemblies, but you would also need the trunk lid as well (I think)

Will

[2mAn]

E30 Aerodynamics

There is a guy making full carbon fiber rear window assemblies, but you would also need the trunk lid as well (I think)



Will

Good place to shed weight.

Is this the guy and parts?

https://www.ebay.com/itm/192122072296

[vitiokas95]

Ok guys I have quite few Air Tab vortex generators left from when I purchased it for my enclosed trailer, where would be good location to mount these on e30 roof? I mean how far from rear window? I have huge ARP wing mounted in the back.

[2mAn]

Ok guys I have quite few Air Tab vortex generators left from when I purchased it for my enclosed trailer, where would be good location to mount these on e30 roof? I mean how far from rear window? I have huge ARP wing mounted in the back.

Heres how I mocked mine up, but honestly I have yet to actually mount them

Untitled by 2mAn

Untitled by 2mAn

[squidmaster]

From my testing I found diminished results anything over 5 on the roof. Of course, I'm using my design as reference so I could be mistaken for those.

[2mAn]

From my testing I found diminished results anything over 5 on the roof. Of course, I'm using my design as reference so I could be mistaken for those.

This article was linked earlier in the thread and it had similar results after 6

http://www.autospeed.com/A_111110/hDg34uLtp_1/cms/article.html

When I talked to the guy selling the airtabs he mentioned the spacing of them, so I felt 7 was the a good number to max out the benefits of the airtabs.

Whats the spacing of your 5?

Is there any benefit placing any on the side of the car? Ive seen people place them on the front sides and rear sides too

[squidmaster]

Sides are helpful, but the front is really the best help

Nah, I understand they probably need different spacing than mine, just weighing in from what I saw in the CFD testing

[Emre]

It was just a cruiser that some butthurt exec decided at the last minute to try and outpace the m3. At least that's my feeling on the matter haha

You've got that backwards

The W201 16v hit the scene in '84 and started winning touring car races by '85. The 2.3L E30s at the time couldn't see which way they went...which is why BMW started developing the E30 further into what eventually became the M3. We didn't see an M3 until '87 ... and it would never have existed if it weren't for the 190E 2.3-16

There's a lot of debate about this part, but some argue that BMW copied quite a lot of the W201 design to turn the E30 into a race winner, particularly the raised rear deck height and angle of the rear glass. There are also some similarities in the shape of the bumpers, front valence, side skirts, and profile of the rear spoiler. They used the same basic engine architecture and same Getrag gearbox.

The reason I say there's a "debate" is that Benz fans like to say BMW copied the aero package and drivetrain. BMW fans say any similarities are coincidental, since they're built to the same rule book. Personally, I buy that argument for the engine: a twin-cam 4-banger clearly made more sense than a SOHC inline-six, and BMW already had the M88 head to play with. But I think Benz guys may have a point when it comes to the aero.

In the DTM series, the E30 M3 and 190E 16v (plus their various Evo versions) won about the same number of races. It's true that the M3 is the "winningest touring car is history," but that's because it was run much more widely. Benz only cared about DTM and did not support any international racing. Any time the 190E and M3 went head-to-head, they performed about the same.

[vitiokas95]

Sides are helpful, but the front is really the best help

Nah, I understand they probably need different spacing than mine, just weighing in from what I saw in the CFD testing

Where would you mount it in front?

[squidmaster]

You've got that backwards

The W201 16v hit the scene in '84 and started winning touring car races by '85. The 2.3L E30s at the time couldn't see which way they went...which is why BMW started developing the E30 further into what eventually became the M3. We didn't see an M3 until '87 ... and it would never have existed if it weren't for the 190E 2.3-16

There's a lot of debate about this part, but some argue that BMW copied quite a lot of the W201 design to turn the E30 into a race winner, particularly the raised rear deck height and angle of the rear glass. There are also some similarities in the shape of the bumpers, front valence, side skirts, and profile of the rear spoiler. They used the same basic engine architecture and same Getrag gearbox.

The reason I say there's a "debate" is that Benz fans like to say BMW copied the aero package and drivetrain. BMW fans say any similarities are coincidental, since they're built to the same rule book. Personally, I buy that argument for the engine: a twin-cam 4-banger clearly made more sense than a SOHC inline-six, and BMW already had the M88 head to play with. But I think Benz guys may have a point when it comes to the aero.

In the DTM series, the E30 M3 and 190E 16v (plus their various Evo versions) won about the same number of races. It's true that the M3 is the "winningest touring car is history," but that's because it was run much more widely. Benz only cared about DTM and did not support any international racing. Any time the 190E and M3 went head-to-head, they performed about the same.

But..... the e30 came out in 82.... the same year as the 190e, and it looked quite similar to the previous e21.... Having owned both, parked side by side, there are many differences and the lines don't match the way you say they do. I mean, besides being an 80s car that all shared the same basic shape... The rear glass is completely different. The trunks are completely different. The hoods are different. The front and read valences aren't even the same basic direction. I mean, prove me wrong please because the history of it is fascinating, but do so with a documentary or some articles or something, because I just don't see any of that from the surface-level.

Naturally the cars would be similar in some ways... they were direct competitors released at the same time from the same country from two companies with a long history of releasing vehicles just to compete with the other.

Then the 2.5L cosworth came out in '88, two years after the m3.... And then the 190e didn't have a single dtm champion until 1992.... meanwhile, the e30 M3 already had two championships by then. The 2.3 cosworth was competing with standard 325iS, and even had fewer HP than a standard 325iS.
It's said that the 2.5 cossie was released specifically to compete with the M3.

M3 - 1986
190 2.5 Cossie - 1988
M3 Evo - 1987
190 Evo - 1989

[ForcedFirebird]

The Cosworth 190e was built to compete with Audi in Rally, not the e30 in DTM. Rally had similar rules for conglomeration, so a road-going de-tuned Cosworth was built for the masses. The Evo I was intended to compete with BMW, but it didn't debut until 1989.