Technical Bulletin--ST3 OEM Aero 5-4-16

[Greg G.]

TECHNICAL BULLETIN 5-4-16

ST3 "OEM Aero" Modification Factor

 

7.3.2

D) ST3 Only Production Vehicle Aerodynamics (does not apply to ST1 or ST2 vehicles)

 

Production vehicles that maintain their unmodified OEM trim model body lines and do not have non-OEM aerodynamic aides or modifications may assess the Modification Factor for “OEM Aero” in calculating the “Adjusted Wt/HP Ratio” (7.4). Under this specific rule, an aerodynamic aide is considered non-OEM if it did not come configured on the vehicle from the manufacturing factory on the competing vehicle's trim model. There is no updating or backdating across trim models or the addition of dealer installed OEM options permitted.

 

Some examples of items not permitted under the "OEM Aero" Modification Factor would be the addition of Z06 or Z07 Aero aides to a base trim Corvette, or the Laguna Seca Aero package on a Mustang GT.

[Ryan S.]

So just simple example...... rich guy shows up with new Z06 (so he has factory aero), where as the not so rich guy shows up with a base stingray with Z06 aero added.... not so rich guy takes it in the shorts because he has the same "factory" aero .

 

Not to be confrontational, but I'm dying to here the argument for parody in this simple example.....

 

Fairness in aerodynamics would be the "base" trim for the model (i.e. the not so rich guy model) is the comparison guideline for if modifications have been made.

[Greg G.]

So just simple example...... rich guy shows up with new Z06 (so he has factory aero), where as the not so rich guy shows up with a base stingray with Z06 aero added.... not so rich guy takes it in the shorts because he has the same "factory" aero .

 

Not to be confrontational, but I'm dying to here the argument for parody in this simple example.....

 

Rich guy would have to detune his car by 100-200+ HP in order to get into ST3, which is too painful to see with his car that fits into ST2 or ST3, and is highly competitive.

 

Or,

 

Rich guy detunes his car by 200+ HP, and a Technical Bulletin comes out the next day.

 

Or,

 

This rule goes away in '17 altogether, and is substituted by a rule that has nothing to do with what comes on the car OEM that applies to both ST3 and ST4.

[Ryan S.]

Rich guy would have to detune his car by 100-200+ HP in order to get into ST3, which is too painful to see with his car that fits into ST2 or ST3, and is highly competitive.

 

Or,

 

Rich guy detunes his car by 200+ HP, and a Technical Bulletin comes out the next day.

 

Or,

 

This rule goes away in '17 altogether, and is substituted by a rule that has nothing to do with what comes on the car OEM that applies to both ST3 and ST4.

 

But the rule was intented to create an equalizer between those that choose aero and those that choose power, correct? Your example highlights how the rule handicaps those that can not start with the more expensive car.

[Greg G.]

But the rule was intented to create an equalizer between those that choose aero and those that choose power, correct? Your example highlights how the rule handicaps those that can not start with the more expensive car.

I don't understand your point. I think my example shows that someone starting with an expensive car (with good OEM aero) that comes OEM with way too much power to be close to being in ST3 or ST4 will not end up competing in ST3 or ST4.

 

I would say that as opposed to the rule handicapping those that cannot start with the more expensive car, I would say that life handicaps those than cannot start with the more expensive __________. (You can fill in "car" or lots of other things here). Here is an example for you, there is no doubt that someone who can afford to throw $500,000 into an amateur race car has an advantage over someone who can only put $25,000 into the car. However, the great equalizer is talent, and we have seen those with much cheaper cars school those with more expensive cars year after year.

[Ryan S.]

I don't understand your point. I think my example shows that someone starting with an expensive car (with good OEM aero) that comes OEM with way too much power to be close to being in ST3 or ST4 will not end up competing in ST3 or ST4.

 

I would say that as opposed to the rule handicapping those that cannot start with the more expensive car, I would say that life handicaps those than cannot start with the more expensive __________. (You can fill in "car" or lots of other things here). Here is an example for you, there is no doubt that someone who can afford to throw $500,000 into an amateur race car has an advantage over someone who can only put $25,000 into the car. However, the great equalizer is talent, and we have seen those with much cheaper cars school those with more expensive cars year after year.

 

I want to be clear, I know cubic dollars is not something that can be written out of the rule book, but I don't see how writing in explicit instructions on how to purchase rule skirting is helpful to class participation.

 

Your example is little more than useless rhetoric, you speak to nothing technical regarding the rule set. The rules allow de-tuning.... or at least don't prevent it, and the classification form allows for multiple tunes and the corresponding class declaration (which makes sense for a power to weight rule). However, the aero rule DOES handicap those that try to create parody between different trim levels of the same model, and that you have offered no justification for .....

[Rob S.]

Hi Greg,

 

Basically, in order to qualify for the "OEM Aero" mod factor, all body panels must be unmodified OEM size and shape, correct? So no hood vents or vented fender liners? Also, it is ok for a base model C6 to be converted to a Grand Sport using all GM body parts that came on the standard Grand Sport (no optional aero parts) and still be considered "OEM Aero"? Thanks.

[davidfarmer]

No, you used to be able to convert (to a Grand Sport for instance) but now you cannot. You can only run your car as the aero came from the factory, for your exact model. BUT hoods have always been open......

[farberio]

 

Wait, you are saying to two cars can be setup completely identically except and have a different modified Pwr/Wt? How exactly is this fair at all, doesn't this just make the pay to play factor higher for almost no reason?

 

Why not just make OEM aero the BASE trim of the vehicle?

 

[davidfarmer]

I guess so, a Z06 Carbon with a factory splitter and factory spoiler can run approx 25 more HP than a normal Z06 that has added those parts....even though they are GM parts.

[Greg G.]

I guess so, a Z06 Carbon with a factory splitter and factory spoiler can run approx 25 more HP than a normal Z06 that has added those parts....even though they are GM parts.

And how does a 500 hp Z06 carbon fit into ST3?

 

Also, the new rules will probably not allow a rear spoiler or a rear wing using this modification factor

[brkntrxn]

I guess so, a Z06 Carbon with a factory splitter and factory spoiler can run approx 25 more HP than a normal Z06 that has added those parts....even though they are GM parts.

And how does a 500 hp Z06 carbon fit into ST3?

 

Also, the new rules will probably not allow a rear spoiler or a rear wing using this modification factor

 

 

Can the 500hp Z06 carbon not be detuned/choked back to 350hp?

[Vettedoctor]

I guess so, a Z06 Carbon with a factory splitter and factory spoiler can run approx 25 more HP than a normal Z06 that has added those parts....even though they are GM parts.

And how does a 500 hp Z06 carbon fit into ST3?

 

Also, the new rules will probably not allow a rear spoiler or a rear wing using this modification factor

 

I think a better question would be where in the rules does it say that a 505 hp Z06 Carbon can't fit into ST3? Or a 638 hp ZR1 for that matter? I can't find it anywhere.

[kbrew8991]

Truck LS are cheap, easy, etc... no need to choke the big engines that much unless you just want to. And if you have to have the nice car's VIN to run the parts as OEM (need not be C7Z either, C7 GS has alot of nice OEM aero too, C6Z or C6 GS, etc.), then that's what you have to do.

[haase1375]

my thoughts only

 

I think only 4 and 6 cyl engines should be allowed in st3 only, no detuning 500 hp++++ engines. if a car makes that kind of hp and TORQUE they should be in st2 or st1.

example just went to race in Kentucky there were only 1 su 1 st1 2 st2 and lots of st3 with the top running st3 a bmw m3 v8.

there need's be more balance in classes just push the v8 into st1 or st2 problem solved.

 

regards to all

[Balroks]

Eh, then you'd have to outlaw supercharged v6's and turbocharged I4's. Anybody can make power AND torque a 100 different ways. If you're trying to make it more humble then mandate a manual tranny only, no paddle, PDK's, seq shifters or any of the fancy stuff. As I believe the car you're referring to has that.

[farberio]

haase is referring to Premo's M3 V8 ST3 car, its a manual trans and not a dog or flappy paddle. Though I am willing to bet it has a whole host of other drivers aids that make it far faster to drive for a novice that aren't counted towards modification points.

 

The car has been post raced dyno'd multiple times and never a DQ. It is detuned so willing to bet its tuned to take full advantage of the AVG HP calculator.

[davidfarmer]

Fly by wire cars can easily be defined for st3 and yes st4. And they will pull to redline and make 600 ft-lb of torque down low. Unless they are specifically outlined, then as originally designed, they are legal.

 

You could also just add a few thousand pounds of lead but that would be horrible tondrive

[davidfarmer]

My next upgrade.....a new VIN

[brkntrxn]

The car has been post raced dyno'd multiple times and never a DQ. It is detuned so willing to bet its tuned to take full advantage of the AVG HP calculator.

 

Show me a podium car that ISN'T optimized to the rules and I will show you a region with little real competition.

[brkntrxn]

my thoughts only

 

I think only 4 and 6 cyl engines should be allowed in st3 only, no detuning 500 hp++++ engines. if a car makes that kind of hp and TORQUE they should be in st2 or st1.

example just went to race in Kentucky there were only 1 su 1 st1 2 st2 and lots of st3 with the top running st3 a bmw m3 v8.

there need's be more balance in classes just push the v8 into st1 or st2 problem solved.

 

regards to all

 

 

Firouz - C'mon on now! What am I supposed to do with a street driven 175hp 1984 Mustang GT with its big bad V8? You have to keep in mind that the ST rules carry over to the TT rules and those cars show up off the street to run in TT3 and TTB (aka TT4).

[farberio]

The car has been post raced dyno'd multiple times and never a DQ. It is detuned so willing to bet its tuned to take full advantage of the AVG HP calculator.

 

Show me a podium car that ISN'T optimized to the rules and I will show you a region with little real competition.

 

I fully agree, I apologise if my post read another way.