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      01-20-2021, 01:34 PM   #67
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I was watching on YouTube and did some reading on the effectiveness of a wing as function of the total weight of the car.

My apologies, but I could not find the reference out there quickly.

From at least two sources, the wing (a real wing, not the GTS spoiler) has very little effect on a 3600Lbs car. It is very helpful for a 2300Lbs - 2600Lbs race car.

While the wing will still generate the downforce, as indicated by the Wing specs, it will not generate the lap time benefits on E92 M3 that was not striped down.

It involves calculations that I am not expert on, but intuitively the G forces as proportion to mass don't help the tires grip more by adding more weight (downforce)

Sorry I can't find the links
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      01-20-2021, 01:41 PM   #68
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Quote:
Originally Posted by rhyary View Post
I was watching on YouTube and did some reading on the effectiveness of a wing as function of the total weight of the car.

My apologies, but I could not find the reference out there quickly.

From at least two sources, the wing (a real wing, not the GTS spoiler) has very little effect on a 3600Lbs car. It is very helpful for a 2300Lbs - 2600Lbs race car.

While the wing will still generate the downforce, as indicated by the Wing specs, it will not generate the lap time benefits on E92 M3 that was not striped down.

It involves calculations that I am not expert on, but intuitively the G forces as proportion to mass don't help the tires grip more by adding more weight (downforce)

Sorry I can't find the links
Yea, that's absolutely true. Normal force (on the tires) to weight ratio is to lateral acceleration as power to weight is to longitudinal acceleration.
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      01-20-2021, 09:20 PM   #69
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Quote:
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Yea, that's absolutely true. Normal force (on the tires) to weight ratio is to lateral acceleration as power to weight is to longitudinal acceleration.
BS. In the paddock it's worth 5 secs per lap. Fact.
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      01-20-2021, 10:53 PM   #70
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Anyone have any pics of the underside of their mounting setups they care to share? Does the gt4/gts setup come through both sheets of sheet metal that make up the trunk and is that suffice? Or does it require reinforcing?
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      01-20-2021, 11:01 PM   #71
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Originally Posted by SAMM3Y View Post
Anyone have any pics of the underside of their mounting setups they care to share? Does the gt4/gts setup come through both sheets of sheet metal that make up the trunk and is that suffice? Or does it require reinforcing?
Highly recommend weld in tubes for any track usage on OE trunk.

Tubes on left.
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      01-20-2021, 11:11 PM   #72
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Originally Posted by SAMM3Y View Post
Anyone have any pics of the underside of their mounting setups they care to share? Does the gt4/gts setup come through both sheets of sheet metal that make up the trunk and is that suffice? Or does it require reinforcing?
Highly recommend weld in tubes for any track usage on OE trunk.

Tubes on left.
Thank you. Trying to picture how they install/weld in and where at the underside of the trunk. The wing I've installed on mine has wide mount points and only is attached currently through the trunk skin with three bolts per side and a rubber seal for water and a small load spreader up top. It flexes if I grab and wiggle it so can imagine under load it flexes and slightly negates any real benefit if there is any, or should I say it's an "adaptive" wing.
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      01-21-2021, 04:18 AM   #73
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Quote:
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Highly recommend weld in tubes for any track usage on OE trunk.

Tubes on left.
I installed reinforcement plates... at the moment 0 problems



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      01-21-2021, 04:21 AM   #74
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Quote:
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Highly recommend weld in tubes for any track usage on OE trunk.

Tubes on left.
I installed reinforcement plates... at the moment 0 problems



This works too, that's how E46 guys reinforce their trunks for GTS wings.
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      01-23-2021, 07:00 PM   #75
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This may help
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      01-23-2021, 07:19 PM   #76
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See at the end.
For heavy car (M3) aero not as effective

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      01-23-2021, 07:47 PM   #77
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Quote:
Originally Posted by rhyary View Post
See at the end.
For heavy car (M3) aero not as effective

That's not what he said in the last video? It's moderate aero won't do much on a heavy car as you need serious aero to see a benefit.

That's very different than aero doesn't benefit heavy cars.
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      01-23-2021, 07:55 PM   #78
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Quote:
Originally Posted by DRLane View Post
Quote:
Originally Posted by rhyary View Post
See at the end.
For heavy car (M3) aero not as effective

That's not what he said in the last video? It's moderate aero won't do much on a heavy car as you need serious aero to see a benefit.

That's very different than aero doesn't benefit heavy cars.
Its complicated and I don't quite understand all of it. But....

If you also study tires, you can see that loading up the tires provide more grip up to a point, from which the rubber give up.

So if you have heavy car, and you load up the tires on top of that in a high speed turn (g-forces) and on top of that add downforce, you are not necessarily going to have more grip.

Now, if you have a light car, that cannot load up the tires by shir g-forces, aero will replace the weight of the heavy car and you gain traction.
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      01-23-2021, 08:01 PM   #79
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Quote:
Originally Posted by rhyary View Post
Quote:
Originally Posted by DRLane View Post
Quote:
Originally Posted by rhyary View Post
See at the end.
For heavy car (M3) aero not as effective

That's not what he said in the last video? It's moderate aero won't do much on a heavy car as you need serious aero to see a benefit.

That's very different than aero doesn't benefit heavy cars.
Its complicated and I don't quite understand all of it. But....

If you also study tires, you can see that loading up the tires provide more grip up to a point, from which the rubber give up.

So if you have heavy car, and you load up the tires on top of that in a high speed turn (g-forces) and on top of that add downforce, you are not necessarily going to have more grip.

Now, if you have a light car, that cannot load up the tires by shir g-forces, aero will replace the weight of the heavy car and you gain traction.
Yeah so it's a system? Substantial aero without additional mechanical grip has diminishing returns.
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      01-23-2021, 08:16 PM   #80
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All I can say is that my aero gained me about 2 seconds at a twisty, slightly sub-2min track. This was with the same tires, but different damper settings.

The car weighed about 3700 with me in it and a full tank. That is quite substantial in my opinion. The same downforce on a lighter car with the same power to weight (and close drag) would no doubt be more effective though.
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      01-23-2021, 08:50 PM   #81
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Quote:
Originally Posted by Bartledoo View Post
All I can say is that my aero gained me about 2 seconds at a twisty, slightly sub-2min track. This was with the same tires, but different damper settings.

The car weighed about 3700 with me in it and a full tank. That is quite substantial in my opinion. The same downforce on a lighter car with the same power to weight (and close drag) would no doubt be more effective though.
How fast are the twisties?

Edit
Bartledoo , I was watching your video, there are no telemetry on your video, but it does not look like you are going fast enough in the turns to generate enough down force for a 3700Lbs car. Is it possible you are just a better driver over time?
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      01-23-2021, 09:48 PM   #82
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This should help:

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      01-23-2021, 09:49 PM   #83
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Quote:
Originally Posted by rhyary View Post
Quote:
Originally Posted by Bartledoo View Post
All I can say is that my aero gained me about 2 seconds at a twisty, slightly sub-2min track. This was with the same tires, but different damper settings.

The car weighed about 3700 with me in it and a full tank. That is quite substantial in my opinion. The same downforce on a lighter car with the same power to weight (and close drag) would no doubt be more effective though.
How fast are the twisties?

Edit
Bartledoo , I was watching your video, there are no telemetry on your video, but it does not look like you are going fast enough in the turns to generate enough down force for a 3700Lbs car. Is it possible you are just a better driver over time?
Seems like you're speaking in absolutes when the videos you're referencing aren't. There are plenty of very fast drivers/cars on this forum that are >3k lbs with substantial aero that unequivocally produce greater grip at the tires as a combination of mechanical and aero. At high speeds and even low speeds.
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      01-23-2021, 10:14 PM   #84
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Quote:
Originally Posted by DRLane View Post
Quote:
Originally Posted by rhyary View Post
Quote:
Originally Posted by Bartledoo View Post
All I can say is that my aero gained me about 2 seconds at a twisty, slightly sub-2min track. This was with the same tires, but different damper settings.

The car weighed about 3700 with me in it and a full tank. That is quite substantial in my opinion. The same downforce on a lighter car with the same power to weight (and close drag) would no doubt be more effective though.
How fast are the twisties?

Edit
Bartledoo , I was watching your video, there are no telemetry on your video, but it does not look like you are going fast enough in the turns to generate enough down force for a 3700Lbs car. Is it possible you are just a better driver over time?
Seems like you're speaking in absolutes when the videos you're referencing aren't. There are plenty of very fast drivers/cars on this forum that are >3k lbs with substantial aero that unequivocally produce greater grip at the tires as a combination of mechanical and aero. At high speeds and even low speeds.
Yes, there are very fast drivers on this forum, but they cannot defy physics. If you are not going over 100mph in a large diameter turn, you are not fast because of aerodynamics. You are fast because of many other factors.

I am over simplifying, but an average E92 M3 @ 3700 Lbs is not dropping 2sec a laptop doing 40-80 mph i turns because of large wing attached to the trunk.

But what do I know, i ran 19" rims.
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      01-23-2021, 10:27 PM   #85
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Quote:
Originally Posted by rhyary View Post
Quote:
Originally Posted by DRLane View Post
Quote:
Originally Posted by rhyary View Post
Quote:
Originally Posted by Bartledoo View Post
All I can say is that my aero gained me about 2 seconds at a twisty, slightly sub-2min track. This was with the same tires, but different damper settings.

The car weighed about 3700 with me in it and a full tank. That is quite substantial in my opinion. The same downforce on a lighter car with the same power to weight (and close drag) would no doubt be more effective though.
How fast are the twisties?

Edit
Bartledoo , I was watching your video, there are no telemetry on your video, but it does not look like you are going fast enough in the turns to generate enough down force for a 3700Lbs car. Is it possible you are just a better driver over time?
Seems like you're speaking in absolutes when the videos you're referencing aren't. There are plenty of very fast drivers/cars on this forum that are >3k lbs with substantial aero that unequivocally produce greater grip at the tires as a combination of mechanical and aero. At high speeds and even low speeds.
Yes, there are very fast drivers on this forum, but they cannot defy physics. If you are not going over 100mph in a large diameter turn, you are not fast because of aerodynamics. You are fast because of many other factors.

I am over simplifying, but an average E92 M3 @ 3700 Lbs is not dropping 2sec a laptop doing 40-80 mph i turns because of large wing attached to the trunk.

But what do I know, i ran 19" rims.
Aero can be and is more than a large wing on a trunk. Which goes back to your videos comment of moderate vs substantial and the requirements to drive meaningful results.

The 19s are great, it's the emphasis on cheap mismatched tire compounds on $20k front brakes that warrants a chuckle
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      01-23-2021, 10:34 PM   #86
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Regardless of the actual science behind this. For the non pro driver aero makes the car easier to drive faster. Basically it’s more stable at higher cornering speeds. So while a stupid wing on the trunk doesn’t seem like it should do much it can actually add seconds to a non pro driver. It’s totally plausible it could add 2-3 seconds a lap.

If you did the same testing with a pro driver who can bang out laps .1 to .2 seconds apart you’ll likely see a marginal difference....
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      01-24-2021, 12:43 AM   #87
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Quote:
Originally Posted by rhyary View Post
Yes, there are very fast drivers on this forum, but they cannot defy physics. If you are not going over 100mph in a large diameter turn, you are not fast because of aerodynamics. You are fast because of many other factors.

I am over simplifying, but an average E92 M3 @ 3700 Lbs is not dropping 2sec a laptop doing 40-80 mph i turns because of large wing attached to the trunk.

But what do I know, i ran 19" rims.
Guy, I'm sorry but you sound like ehhh. And for reference, I put the wing AND splitter on and after 8 months without being in the car or on a track I was over a second faster the first day in the car and 2 seconds faster the next day at the track. But sure I just magically got that much faster by not driving. Also you completely ignore braking and exit.

For reference turn 1 on the track is from 141mph to 110mph apex, then there are two other 115-120mph runs with big braking zones, a 100+mph downhill right turn into a big braking zone, a 115mph crest turn, etc.

I'm also not using a baby wing, and have a 5" splitter with medium tunnels.
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      01-24-2021, 04:32 AM   #88
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Quote:
Originally Posted by Bartledoo View Post
Quote:
Originally Posted by rhyary View Post
Yes, there are very fast drivers on this forum, but they cannot defy physics. If you are not going over 100mph in a large diameter turn, you are not fast because of aerodynamics. You are fast because of many other factors.

I am over simplifying, but an average E92 M3 @ 3700 Lbs is not dropping 2sec a laptop doing 40-80 mph i turns because of large wing attached to the trunk.

But what do I know, i ran 19" rims.
Guy, I'm sorry but you sound like ehhh. And for reference, I put the wing AND splitter on and after 8 months without being in the car or on a track I was over a second faster the first day in the car and 2 seconds faster the next day at the track. But sure I just magically got that much faster by not driving. Also you completely ignore braking and exit.

For reference turn 1 on the track is from 141mph to 110mph apex, then there are two other 115-120mph runs with big braking zones, a 100+mph downhill right turn into a big braking zone, a 115mph crest turn, etc.

I'm also not using a baby wing, and have a 5" splitter with medium tunnels.
That works.
I couldn't tell from your video
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