Daytona 2024

[blacksheep-1]

Restrictor plates in NASCAR have one purpose. To keep the cars out of the stands.

Yep, when cars started flying is when the restrictor plates started, especially after Bobby Allison's flight at Talledega where parts of the car actually went into the stands. One reason you don't see Indycars on some tracks is because spectators were killed in both CART and IRL races at superspeedways. I'd love to see Indy cars at Daytona... never gonna happen. They hit about 245 at Indy, they'd probably bounce 275 at Daytona.
The trade off is that it means " closer" racing, but it creates too many wrecks and not enough competition. Too much depends on luck.

 

[302BOB]

Luck was always your friend at the super speedways.........now more than ever........just ask William Byron..........don't bother Logano about luck today.............

 

[TMSBOSS]

The Daytona 500. I’ve been there. I even attended a drivers meeting, way cool.
The event is a study in marketing. They sell out and folks love the show. The race, well, it sucked and people still loved the event. Watching the best of the best slow down by 2-4 seconds a lap to win the mileage war in each segment, not racing at its best.
I guess if you want to sell a mediocre race which is usually delayed by weather, you simply turn it into a mega event. Marketing, not racing , at its best.

 

[302BOB]

You are right TMS...........The Daytona 500 is not what it used to be............but it gets a lot of attention and still sells a lot of tickets............I'm glad I was around to see Dale win his......

 

[bauern]

Back to the Rolex 24:

Ferrari and BMW lose GT manufacturer points from Daytona

BMW and Ferrari have lost all their IMSA WeatherTech SportsCar Championship and Michelin Endurance Cup manufacturers points from the Rolex 24 At Daytona for the GTD PRO and GTD classes. Both manufa…

racer.com

"BMW and Ferrari have lost all their IMSA WeatherTech SportsCar Championship and Michelin Endurance Cup manufacturers points from the Rolex 24 At Daytona for the GTD PRO and GTD classes. Both manufacturers were found to have performance in excess of IMSA’s expectations. That includes the GTD PRO victory points for Ferrari (Risi Competizione) and third-place points for BMW (Paul Miller Racing). Ferrari had a best finish of second in GTD with AF Corse.

According to the penalty notice for Ferrari: “The IMSA Technical Committee and the IMSA supervisory officials have unanimously determined that Ferrari’s demonstrated performance in the Daytona 24-hour race exceeded IMSA’s expectations as shared in the GT Manufacturers Technical Working Groups. The goal was to ensure the demonstrated performance of the best example of each manufacturer’s car model would be within a targeted performance window — allowing for competitive equivalency.” The notice for BMW read similarly."

Finishing positions are unchanged.

 

[blacksheep-1]

Back to the Rolex 24:

Ferrari and BMW lose GT manufacturer points from Daytona

BMW and Ferrari have lost all their IMSA WeatherTech SportsCar Championship and Michelin Endurance Cup manufacturers points from the Rolex 24 At Daytona for the GTD PRO and GTD classes. Both manufa…

racer.com

"BMW and Ferrari have lost all their IMSA WeatherTech SportsCar Championship and Michelin Endurance Cup manufacturers points from the Rolex 24 At Daytona for the GTD PRO and GTD classes. Both manufacturers were found to have performance in excess of IMSA’s expectations. That includes the GTD PRO victory points for Ferrari (Risi Competizione) and third-place points for BMW (Paul Miller Racing). Ferrari had a best finish of second in GTD with AF Corse.

According to the penalty notice for Ferrari: “The IMSA Technical Committee and the IMSA supervisory officials have unanimously determined that Ferrari’s demonstrated performance in the Daytona 24-hour race exceeded IMSA’s expectations as shared in the GT Manufacturers Technical Working Groups. The goal was to ensure the demonstrated performance of the best example of each manufacturer’s car model would be within a targeted performance window — allowing for competitive equivalency.” The notice for BMW read similarly."

Finishing positions are unchanged.

" exceeded performance expectation" give me a break, the whole ROAR deal is a sandbag fest. We didn't and they bent us over the fence. Too bad about Risi, those guys are funnier than an outhouse rat, I was stuck in an airport with those guys once.
I wonder if the pulled any credentials, and why they didn't give specifics?

 

[Dave_W]

Manufacturers lost their points, but teams and drivers did not? At least they should have penalized the teams & drivers that participated in the sandbagging during the BoP-setting sessions.

 

[steveespo]

The rules fix the wing at a specific spot, the uprights are more open. I'm sure that's the reason the uprights mount to the chassis over ( or close to) the spring pockets. On the Gt4, they use the trunk hinge points.. but, a lever is still a lever, and a longer one will apply more force than a shorter one, so a longer lever that attaches the same size wing ( it's actually a bit smaller) over the suspension points seems to have it all over one that goes 90 degrees to the deck lid. IDK, not an engineer, but I did stay at a Holiday Inn Express the other night.

This^^. I know AJ argues that the force is transmitted through the rear axle regardless of wing position, but the force applied is increased by the lever length. Effective lever length is what makes the difference not upright position. https://r.search.yahoo.com/_ylt=Awr...3252.pdf/RK=2/RS=b2NqkKzfg57JpYdbaATF7aBh6gM-

 

[JAJ]

Hmmm... I'm with AJ on this one. The wing's downforce acts at a distance behind and above (or below) the car's pitch center. The car's pitch center is like the car's roll center, except it's about fore-aft attitude (pitch) changes under changing suspension loads. The wing's downforce rotates the chassis around the pitch center, compressing the rear suspension and extending the front suspension, shifting weight (traction) to the rear tires. So long as the link connecting the wing to the chassis isn't flexible, it's shape and mounting points are irrelevant to how the wing's downforce affects the front and rear axle loads. I expect that the reason Ford chose to run the GT3/GT4 wing mounts forward to the C pillar is because it reduces drag.

 

[Dave_W]

Pitch center - a new term I've learned.

Consider this drawing of a wing with traditional vertical upright attaching it to a seesaw. The fulcrum is the car's pitch center, and we want to apply the downforce produced by the rear wing to the rear tire's contact patch. The force we're concerned with is represented by the arrow at the axle, and it is directly proportional to the downforce of the rear wing by a factor of the distances from the pitch center to the tire's contact patch vs. the pitch center to the rear wing's center of pressure (the point of the arrow above the wing). For the sake of simplicity, let's say that the combination of the green wing mount and the seesaw are an infinitely stiff structure.

Now, we change the vertical upright to a large triangular shape - has the force at the axle arrow changed if the downforce of the wing has not? I'd argue no, because the distances of the two arrows to the fulcrum have not changed.


Now let's remove a portion of that triangular shape. Again, has the force at the axle arrow changed? I'd again argue no, as the distances of the two arrows relative to the fulcrum have not changed.


So where the wing is attached to the seesaw (or car) doesn't really matter, as long as the position of the fulcrum / pitch center, the wing's CoP, and tire's contact patch are the same.

 

[blacksheep-1]

Pitch center - a new term I've learned.

Consider this drawing of a wing with traditional vertical upright attaching it to a seesaw. The fulcrum is the car's pitch center, and we want to apply the downforce produced by the rear wing to the rear tire's contact patch. The force we're concerned with is represented by the arrow at the axle, and it is directly proportional to the downforce of the rear wing by a factor of the distances from the pitch center to the tire's contact patch vs. the pitch center to the rear wing's center of pressure (the point of the arrow above the wing). For the sake of simplicity, let's say that the combination of the green wing mount and the seesaw are an infinitely stiff structure.
View attachment 93387
Now, we change the vertical upright to a large triangular shape - has the force at the axle arrow changed if the downforce of the wing has not? I'd argue no, because the distances of the two arrows to the fulcrum have not changed.
View attachment 93388

Now let's remove a portion of that triangular shape. Again, has the force at the axle arrow changed? I'd again argue no, as the distances of the two arrows relative to the fulcrum have not changed.
View attachment 93389

So where the wing is attached to the seesaw (or car) doesn't really matter, as long as the position of the fulcrum / pitch center, the wing's CoP, and tire's contact patch are the same.

Good info, but I disagree, as an example, on drag cars, if you run the springs behind the axle vs in front of the axle, the car sees that as a longer wheelbase, and acts accordingly. The top fuel guys did the same thing, a small wing further back on a longer mount creates the same pressure as a larger wing over the axle. This means less drag at the same result. I'm saying that is what Ford is trying to do with the cantilevered Gt3 andGt4 wings.

 

[PatrickStapler]

I agree with BS-1. It's almost like a torque wrench affect. There's an advantage gained (moment) from the wing arms going forward versus just straight down.

 

[steveespo]

Pitch center - a new term I've learned.

Consider this drawing of a wing with traditional vertical upright attaching it to a seesaw. The fulcrum is the car's pitch center, and we want to apply the downforce produced by the rear wing to the rear tire's contact patch. The force we're concerned with is represented by the arrow at the axle, and it is directly proportional to the downforce of the rear wing by a factor of the distances from the pitch center to the tire's contact patch vs. the pitch center to the rear wing's center of pressure (the point of the arrow above the wing). For the sake of simplicity, let's say that the combination of the green wing mount and the seesaw are an infinitely stiff structure.
View attachment 93387
Now, we change the vertical upright to a large triangular shape - has the force at the axle arrow changed if the downforce of the wing has not? I'd argue no, because the distances of the two arrows to the fulcrum have not changed.
View attachment 93388

Now let's remove a portion of that triangular shape. Again, has the force at the axle arrow changed? I'd again argue no, as the distances of the two arrows relative to the fulcrum have not changed.
View attachment 93389

So where the wing is attached to the seesaw (or car) doesn't really matter, as long as the position of the fulcrum / pitch center, the wing's CoP, and tire's contact patch are the same.

Where the force is transferred to the track is not in question Dave, it is the amount generated by the assembly. If the wing makes 400 lbs @ 100 mph in either example, the amount of force sent into the chassis at 90 degrees (illustration A) will be 400 lbs. The force applied in (Illustration B) say 45 degree over a 2 foot length will be a Torque force equal to; T=r*F*sin<. Sine of 45 degrees is .7071, r= 2 feet, F= 400 lbs. So the applied force at the connection is 566 lbs. So as @blacksheep-1 says, they can use a trimmer less draggy wing to equal the downforce of the conventional mounting.

 

[JAJ]

Where the force is transferred to the track is not in question Dave, it is the amount generated by the assembly. If the wing makes 400 lbs @ 100 mph in either example, the amount of force sent into the chassis at 90 degrees (illustration A) will be 400 lbs. The force applied in (Illustration B) say 45 degree over a 2 foot length will be a Torque force equal to; T=r*F*sin<. Sine of 45 degrees is .7071, r= 2 feet, F= 400 lbs. So the applied force at the connection is 566 lbs. So as @blacksheep-1 says, they can use a trimmer less draggy wing to equal the downforce of the conventional mounting

The force that affects the axle comes from the chassis. It doesn't matter how the wing is attached to the chassis, the location of the wing relative to the chassis and relative to the axle doesn't change from one bolting location to the other.

Think about it this way - if you look at @Dave_W's middle diagram, the triangle bracket can be bolted near the axle to work as a 45 degree brace between the chassis and the wing or it can be bolted directly below the wing to work as a straight-down brace. As a starting point, lets imagine that we put bolts at both ends of the bottom of the triangle and they're done in such a way that the bracket can't move if you take bolts out of one end or the other.

Now, take the bolts out of the brace directly below the wing. What happens? Well, we have the effect of the 45 degree brace, but when you load up the wing, the brace and the chassis move together as though those bolts below the wing are still in place, even if they aren't. If there's 400 pounds pushing directly down on the wing, both the chassis and the point on the bracket directly below the wing where it's beside the chassis will move the same distance as they would if the bolts were still in place.

Now put those bolts back in and take out the bolts near the axle. Now the only attachment is at the back directly below the wing. Once again, when the wing loads up, the brace near the axle continues to move with the chassis as though the bolts near the axle were still in place, even if they aren't. If there's 400 pounds pushing down on the wing, the point on the chassis directly below the wing will move the distance it would with the bolts in place because those bolts are in place.

This gedankenexperiment demonstrates that regardless of where you bolt the bracket to the chassis, one end, the other end or both ends, the wing, the bracket and the chassis move together in exactly the same way under downward pressure from the wing. Taking the bolts out at one end or the other of the triangle brace doesn't change the downforce. The only thing that makes a difference is taking both sets out, a choice that reduces downforce to zero.

 

[bauern]

Where the force is transferred to the track is not in question Dave, it is the amount generated by the assembly. If the wing makes 400 lbs @ 100 mph in either example, the amount of force sent into the chassis at 90 degrees (illustration A) will be 400 lbs. The force applied in (Illustration B) say 45 degree over a 2 foot length will be a Torque force equal to; T=r*F*sin<. Sine of 45 degrees is .7071, r= 2 feet, F= 400 lbs. So the applied force at the connection is 566 lbs. So as @blacksheep-1 says, they can use a trimmer less draggy wing to equal the downforce of the conventional mounting.

Just want to point out that there is a lever arm in illustration A also as the wing is attached a distance behind the axle.
Blacksheep's dragster example uses distance to gain advantage (no lever arm vs a lever arm).

 

[bauern]

The force that affects the axle comes from the chassis. It doesn't matter how the wing is attached to the chassis, the location of the wing relative to the chassis and relative to the axle doesn't change from one bolting location to the other.

Think about it this way - if you look at @Dave_W's middle diagram, the triangle bracket can be bolted near the axle to work as a 45 degree brace between the chassis and the wing or it can be bolted directly below the wing to work as a straight-down brace. As a starting point, lets imagine that we put bolts at both ends of the bottom of the triangle and they're done in such a way that the bracket can't move if you take bolts out of one end or the other.

Now, take the bolts out of the brace directly below the wing. What happens? Well, we have the effect of the 45 degree brace, but when you load up the wing, the brace and the chassis move together as though those bolts below the wing are still in place, even if they aren't. If there's 400 pounds pushing directly down on the wing, both the chassis and the point on the bracket directly below the wing where it's beside the chassis will move the same distance as they would if the bolts were still in place.

Now put those bolts back in and take out the bolts near the axle. Now the only attachment is at the back directly below the wing. Once again, when the wing loads up, the brace near the axle continues to move with the chassis as though the bolts near the axle were still in place, even if they aren't. If there's 400 pounds pushing down on the wing, the point on the chassis directly below the wing will move the distance it would with the bolts in place because those bolts are in place.

This gedankenexperiment demonstrates that regardless of where you bolt the bracket to the chassis, one end, the other end or both ends, the wing, the bracket and the chassis move together in exactly the same way under downward pressure from the wing. Taking the bolts out at one end or the other of the triangle brace doesn't change the downforce. The only thing that makes a difference is taking both sets out, a choice that reduces downforce to zero.

Math says there is a difference with the above parameters. It's actually to the benefit of the vertical mount by 1 lbs. I initially thought that the longer arm of the GT3/4 mount was advantageous. I think it's because the force of the wing is not acting on the arm at 90*. The longer arm of the 45* mount isn't enough to over come the angle between it and the wing force.

 

[302BOB]

All this math stuff is giving me a headcahe............I'm still trying to figure out what "The dish pistons are optimized by the compression ratio" means.......Hon, Where's those advils!!!!!!!!!

 

[302BOB]

How about that finish at Atlanta Sunday!?!?!?!!!....3 cars a nose apart at the checker!!!!!!!!!!!!!!!!........I thought Blaney had it ....................Congrats to Daniel Suarez!!!!!!!!!!!

 

[Dave_W]

So the applied force at the connection is 566 lbs.

But that's the force at the connection of the wing upright to the chassis - you then need to calculate the leverage that connection point has on the axle based on it's distance from the fulcrum (pitch center) to find the effective change in downward pressure on the contact patch. I'm pretty sure it cancels out.

 

[Dave_W]

The top fuel guys did the same thing, a small wing further back on a longer mount creates the same pressure as a larger wing over the axle. T

That's changing the distance between the rear axle and the wing, which does change the leverage of the wing's downforce on the rear tire contact patch.

I'm saying that is what Ford is trying to do with the cantilevered Gt3 andGt4 wings.

I'll admit I don't know the details; my assumption is that the position of the rear wing (relative to the body, which also means rear axle) is dictated by the rules, and does not change if the wing uprights are vertical vs. cantilevered. So the distance from the rear wing to the rear axle does not change in this case.