Street Prepared - Rear Spoiler Question
11-28-2016, 09:28 PM
#1
Racer
Thread Starter
Street Prepared - Rear Spoiler Question
The Street Prepared rules read like this with regards to rear spoilers.
"The spoiler may extend no more than 10” (254 mm) from the original bodywork in any direction. The spoiler may be no wider than the original bodywork, and it shall not protrude beyond the overall perimeter of the bodywork as viewed from above."
Innovative Auto Creations make's a nice Wickerbill Spoiler modeled off of the C7 Z06's Stage 3 Spoiler that I'd really like to use however I'm not sure if it's compliant with the rules or not though.
This is what it looks like:
I realize this won't give the same performance gains as a true custom made rear spoiler but I'm also not reading to start hacking up my rear hatch or bumper cover if I can avoid it.
"The spoiler may extend no more than 10” (254 mm) from the original bodywork in any direction. The spoiler may be no wider than the original bodywork, and it shall not protrude beyond the overall perimeter of the bodywork as viewed from above."
Innovative Auto Creations make's a nice Wickerbill Spoiler modeled off of the C7 Z06's Stage 3 Spoiler that I'd really like to use however I'm not sure if it's compliant with the rules or not though.
This is what it looks like:
I realize this won't give the same performance gains as a true custom made rear spoiler but I'm also not reading to start hacking up my rear hatch or bumper cover if I can avoid it.
Last edited by 94boosted; 11-28-2016 at 11:58 PM.
11-29-2016, 08:53 AM
#3
Melting Slicks
That's a rather poorly written rule, since a spoiler at any angle at all (such as shown) will stick out beyond the perimeter of the bodywork when viewed from above. I realize the idea is to prevent the spoiler from sticking out aft of the bodywork, but any spoiler will and should stick out a bit.
Since on the later Corvette the most rearward part of the bumper cover is the aft perimeter of the car you're kinda screwed with that spoiler.
Most who've done spoilers on Corvettes have used a simple sheet metal spoiler and mounted it between the body and the bumper cover, which works and meets the rules as written.
What you have here is a typical spoiler that is a production item and is designed for the aftermarket, which have to look decent and be easy to fit by the typical enthusiast. Since it wasn't designed to meet the letter of the rules it's not correct, but it's not a performance advantage compared to a legal spoiler.
About the only thing you can do is write a letter and get a clarification and see if the SEB will either ok that spoiler as being within the spirit of the rules. You could ask for an allowance aft of the rearmost part of the bodywork for cars where the rearmost part of the body is the upper body surface.
The problem is that the SEB will likely say they don't have the time to approve every aftermarket spoiler and that while this is not a performance advantage it doesn't meet the letter of the rules. If you suggest a rule change that is something that allows mass produced aftermarket spoilers to protrude x inches aft of the bodywork on cars where the rear upper edge of the bodywork is the outside perimeter you might have a shot. Something like that could be done as a clarification (allow it immediately) and they could publish it in Fasttrack and incorporate it into next years rules. All of this is a long shot, but that's about all you've got.
If you showed up with this setup at a local event nobody is going to care and you won't get protested. Even at nationals, since the spoiler isn't that tall, the protest committee isn't going to throw you out, they're just going to slap your wrist and say don't come back with that next year...
I'd write the letter and just use it if that's what you like and don't worry too much about it.
Since on the later Corvette the most rearward part of the bumper cover is the aft perimeter of the car you're kinda screwed with that spoiler.
Most who've done spoilers on Corvettes have used a simple sheet metal spoiler and mounted it between the body and the bumper cover, which works and meets the rules as written.
What you have here is a typical spoiler that is a production item and is designed for the aftermarket, which have to look decent and be easy to fit by the typical enthusiast. Since it wasn't designed to meet the letter of the rules it's not correct, but it's not a performance advantage compared to a legal spoiler.
About the only thing you can do is write a letter and get a clarification and see if the SEB will either ok that spoiler as being within the spirit of the rules. You could ask for an allowance aft of the rearmost part of the bodywork for cars where the rearmost part of the body is the upper body surface.
The problem is that the SEB will likely say they don't have the time to approve every aftermarket spoiler and that while this is not a performance advantage it doesn't meet the letter of the rules. If you suggest a rule change that is something that allows mass produced aftermarket spoilers to protrude x inches aft of the bodywork on cars where the rear upper edge of the bodywork is the outside perimeter you might have a shot. Something like that could be done as a clarification (allow it immediately) and they could publish it in Fasttrack and incorporate it into next years rules. All of this is a long shot, but that's about all you've got.
If you showed up with this setup at a local event nobody is going to care and you won't get protested. Even at nationals, since the spoiler isn't that tall, the protest committee isn't going to throw you out, they're just going to slap your wrist and say don't come back with that next year...
I'd write the letter and just use it if that's what you like and don't worry too much about it.
The following users liked this post:
94boosted (11-29-2016)
11-29-2016, 09:34 AM
#4
Melting Slicks
That spoiler doesn't stick out more than 10 inches wider than the body, nor does it extend more than 10 inches further back then the rearmost part of the body. If there is any question at all about the height then loosen the four adjustment bolts and slide the wickerbill down some. At the end of the day just extend it back out to where you had it and drive home again.
I can't think that many regional events would bother you about it at all.
I can't think that many regional events would bother you about it at all.
11-29-2016, 09:57 AM
#6
That spoiler doesn't stick out more than 10 inches wider than the body, nor does it extend more than 10 inches further back then the rearmost part of the body. If there is any question at all about the height then loosen the four adjustment bolts and slide the wickerbill down some. At the end of the day just extend it back out to where you had it and drive home again.
I can't think that many regional events would bother you about it at all.
I can't think that many regional events would bother you about it at all.
The yellow Z in your next picture has the spoiler attached at the bolts where the rear bumper meets the rear bucket. It sticks up between the hatch and bumper. It's an easy 2-3" forward of the rear face of the bumper. It basically sticks straight up and does not protrude past the rear face of the bumper. Therefore, it's legal.
11-29-2016, 10:12 AM
#7
Melting Slicks
But it does stick past the perimeter of the body when viewed from above. It doesn't meet the rules. That was the original question. They may not bother him about it, yes, but according to the rules it's not allowed.
The yellow Z in your next picture has the spoiler attached at the bolts where the rear bumper meets the rear bucket. It sticks up between the hatch and bumper. It's an easy 2-3" forward of the rear face of the bumper. It basically sticks straight up and does not protrude past the rear face of the bumper. Therefore, it's legal.
The yellow Z in your next picture has the spoiler attached at the bolts where the rear bumper meets the rear bucket. It sticks up between the hatch and bumper. It's an easy 2-3" forward of the rear face of the bumper. It basically sticks straight up and does not protrude past the rear face of the bumper. Therefore, it's legal.
11-29-2016, 11:06 AM
#8
Instructor
I'm on the **** (street prepared advisory committee) and as stated previously the spoiler in question does not meet the letter of the rule since it extends
over the perimeter of the body as viewed from above. That being said at a national event where protests happen in my opinion no one would care about this spoiler since it doesn't provide an advantage over a 10" legal one.
over the perimeter of the body as viewed from above. That being said at a national event where protests happen in my opinion no one would care about this spoiler since it doesn't provide an advantage over a 10" legal one.
The following users liked this post:
94boosted (11-29-2016)
11-29-2016, 11:12 AM
#9
Racer
Thread Starter
That's a rather poorly written rule, since a spoiler at any angle at all (such as shown) will stick out beyond the perimeter of the bodywork when viewed from above. I realize the idea is to prevent the spoiler from sticking out aft of the bodywork, but any spoiler will and should stick out a bit.
Since on the later Corvette the most rearward part of the bumper cover is the aft perimeter of the car you're kinda screwed with that spoiler.
Most who've done spoilers on Corvettes have used a simple sheet metal spoiler and mounted it between the body and the bumper cover, which works and meets the rules as written.
What you have here is a typical spoiler that is a production item and is designed for the aftermarket, which have to look decent and be easy to fit by the typical enthusiast. Since it wasn't designed to meet the letter of the rules it's not correct, but it's not a performance advantage compared to a legal spoiler.
About the only thing you can do is write a letter and get a clarification and see if the SEB will either ok that spoiler as being within the spirit of the rules. You could ask for an allowance aft of the rearmost part of the bodywork for cars where the rearmost part of the body is the upper body surface.
The problem is that the SEB will likely say they don't have the time to approve every aftermarket spoiler and that while this is not a performance advantage it doesn't meet the letter of the rules. If you suggest a rule change that is something that allows mass produced aftermarket spoilers to protrude x inches aft of the bodywork on cars where the rear upper edge of the bodywork is the outside perimeter you might have a shot. Something like that could be done as a clarification (allow it immediately) and they could publish it in Fasttrack and incorporate it into next years rules. All of this is a long shot, but that's about all you've got.
If you showed up with this setup at a local event nobody is going to care and you won't get protested. Even at nationals, since the spoiler isn't that tall, the protest committee isn't going to throw you out, they're just going to slap your wrist and say don't come back with that next year...
I'd write the letter and just use it if that's what you like and don't worry too much about it.
Since on the later Corvette the most rearward part of the bumper cover is the aft perimeter of the car you're kinda screwed with that spoiler.
Most who've done spoilers on Corvettes have used a simple sheet metal spoiler and mounted it between the body and the bumper cover, which works and meets the rules as written.
What you have here is a typical spoiler that is a production item and is designed for the aftermarket, which have to look decent and be easy to fit by the typical enthusiast. Since it wasn't designed to meet the letter of the rules it's not correct, but it's not a performance advantage compared to a legal spoiler.
About the only thing you can do is write a letter and get a clarification and see if the SEB will either ok that spoiler as being within the spirit of the rules. You could ask for an allowance aft of the rearmost part of the bodywork for cars where the rearmost part of the body is the upper body surface.
The problem is that the SEB will likely say they don't have the time to approve every aftermarket spoiler and that while this is not a performance advantage it doesn't meet the letter of the rules. If you suggest a rule change that is something that allows mass produced aftermarket spoilers to protrude x inches aft of the bodywork on cars where the rear upper edge of the bodywork is the outside perimeter you might have a shot. Something like that could be done as a clarification (allow it immediately) and they could publish it in Fasttrack and incorporate it into next years rules. All of this is a long shot, but that's about all you've got.
If you showed up with this setup at a local event nobody is going to care and you won't get protested. Even at nationals, since the spoiler isn't that tall, the protest committee isn't going to throw you out, they're just going to slap your wrist and say don't come back with that next year...
I'd write the letter and just use it if that's what you like and don't worry too much about it.
How does one even go about writing and sending the letter? I’ve poked around on the SCCA website but I’m having no luck.
11-29-2016, 11:14 AM
#10
Racer
Thread Starter
No I've spoken with the manufacturer and they've confirmed that the winglet does overhang the back lip of the bumper cover by ~1/2"
11-29-2016, 11:17 AM
#11
Racer
Thread Starter
I'm on the **** (street prepared advisory committee) and as stated previously the spoiler in question does not meet the letter of the rule since it extends
over the perimeter of the body as viewed from above. That being said at a national event where protests happen in my opinion no one would care about this spoiler since it doesn't provide an advantage over a 10" legal one.
over the perimeter of the body as viewed from above. That being said at a national event where protests happen in my opinion no one would care about this spoiler since it doesn't provide an advantage over a 10" legal one.
Allow mass produced aftermarket spoilers to protrude 1 inch aft of the bodywork on cars where the rear upper edge of the bodywork is the outside perimeter.
12-18-2016, 07:13 PM
#12
12-18-2016, 11:01 PM
#13
Its mounted at the base using a custom bracket its just two L shape bends with cotter pins holding them in.
then the supports are from longacre http://www.longacreracing.com/produc...s+-+8%22+Black
The spoiler itself is cut out of a sheet of polycarbonate.
12-19-2016, 10:16 AM
#14
12-19-2016, 06:41 PM
#15
Like an upside down T thats just bolted down to the rear bumper?
12-20-2016, 08:07 AM
#17
Here is a picture of Marc Monnar's DSP car. It's all I could find quickly but you get the idea.
12-23-2016, 12:13 AM
#18
Racer
Thread Starter
It's a work in progress still.
The following users liked this post:
383 (12-23-2016)
12-23-2016, 06:01 AM
#19
12-23-2016, 08:38 AM
#20
Melting Slicks
Looks good, probably overkill in terms of strength, could be half as thick and it would probably be fine. Remember that if there is a bit of curvature in the surface it will be stiff as all get out....
Last edited by Solofast; 12-23-2016 at 08:38 AM.