1.2.3
Interpreting the GCR shall not be strained or tortured and applying the GCR shall be logical .....
So if a simple magnet doesn't stick to it... it must be non-ferrous.
1.2.3
Interpreting the GCR shall not be strained or tortured and applying the GCR shall be logical .....
So if a simple magnet doesn't stick to it... it must be non-ferrous.
Wren - read my last comment after thinking about it some more - the 2" above the floor thing.
If I get protested and lose Wren, then I would protest every single FC car with a diffuser. I'd pick a horizontal plane 2" above the floor. The sidepod width is typically max width, then the sidepods gradually slope inwards while attached to the top of the diffuser. Then, at that plane, the diffuser upslope becomes wider than the teardrop shape of the sidepod - thereby making the diffuser illegal.
With this rule and thought process, all 5 of the FC's I've had would be illegal:
RF96, RF93, 94/95 Citation, RF99, 08 Citation.
Wren - you're right there.... behind the axle centerline...
How about using this:
Allowances shall be made for radius of bodywork along primarily horizontal surfaces in this area.
Last edited by RobLav; 02.27.13 at 1:13 AM. Reason: Adding stuff
I am unaware of any car that has side pods reaching the rear axle centerline.Originally Posted by RobLav
Wrong thread, but choosing an interpretation that is not in line with engineering industry standards or the gcr definition of ferrous is not going to pass the sniff test. I posted what the stewards had to say in the thread for that discussion.
My RF93, RF96, and 94 Citation (and current one) had (have) bodywork attached to the LD200 aft of the axle centerline. Technically not sidepods but still bodywork.I am unaware of any car that has side pods reaching the rear axle centerline.
But after midnight i like to pull your string just to keep you going.
To keep the F2000 impound from being tortured or strained, instead of carrying a ASME or ASTM manual around i just carry a little magnet in the palm of my hand.
Mike you asked and here is what I remember:
The FF rule about body work width was put into the GCR in response to the Reynard fairings around the rear rockers. They were deemed to be in the shape of an airfoil and under the no wing rule some thought they were illegal. Up to the advent of the Reynard, the body work could not increase in width past the roll bar. That version or interpertation of FF rules goes back to the ADF.
Carrying that rule over to the FC is probably a mistake and should not be interpreted as it is.
So it goes back to that pesky Adrian.
9.1.1.6.f
deals with forward facing gaps in the bodywork and specifically bans there use for creating downforce and also calls for all air passing thru such ducts to pass thru coolers. I can think of I brand of diffuser thats been in use since 2009 on VD's 1st and now the Radon that very likely falls foul of that rule. If we are going to open this can of worms then lets really open it. I dont see how a " double decker" diffuser passes this rule. Happy to be proven incorrect.
Last edited by KevinFirlein; 02.27.13 at 5:48 PM.
Kevin Firlein Autosport,Inc.
Runoffs 1 Gold 3 Silver 3 bronze, 8 Divisional , 6 Regional Champs , 3x Drivers of the year awards
History
The bodywork widening post rear axle came about years ago in FF and was carried over to FC as the FF guys tried to widen and lengthen the tails for downforce as wings and aerofoils were not allowed.
Its always applied to FC bodywork (inc diffusers) so it didn't change for 2013. Stan and I had the conversation on the Dauntless diffuser 2-3 years ago and agreed to diagree then. He felt that diffusers were under a seperate mandate. Frogs method of measuring the thing was discussed and it would probably not pass muster with the COA but works for him. The theoretical section that makes all diffusers illegal that Renn and Stan brought up just doesn't fly in real world enforcement.
Phil
this whole thread makes my brain hurt.
it's **** like this that is making me want to get out of F2K.
Awww, come on guys, it's so simple. Maybe you need a refresher course. Hey! It's all ball bearings nowadays.
Well, then you could race USF where they just tell you what exactly what diffuser to use and charge you an arm and a leg for the privilege... think of it as a convenience charge for removing the headache of having to think
GCR Question
9.1.1.4. Bodywork (page 260)
9.1.1.4.c Bodywork and rear spoiler(s) and any attached components except for suspension components shall not exceed a maximum width of 95cm (37.40 inches). No part of the bodywork, rear spoiler or exhaust system shall extend more than 100cm (39.37 inches) FF; 80cm (31.50 inches) FC behind the centerline of the rear axle nor exceed in height a horizontal plane 90cm (35.43 inches) above the ground with the car as qualified or raced with the driver on board. The safety roll bar/roll cage, fairings, and engine air box are not included in these restrictions. Bodywork shall not increase in width behind the centerline of the rear axle in any horizontal plane. Allowances shall be made for radius of bodywork along primarily horizontal surfaces in this area. Undertrays and floorpans may extend laterally past cockpit sides, sidepods, and engine compart*ment enclosures,
9.1.1.4.d. Diffusers and undertrays shall not exceed a maximum width of 95 cm (37.40 inches). No part of the diffuser or undertray shall extend more than 80 cm (31.50 inches) behind the centerline of the rear axle nor exceed in height a horizontal plane 90cm (35.43 inches) above the ground with the car as qualified or raced with the driver on board. (page 260)
************************************************** *************************
Reading 9.1.1.4.c
It seems pretty clear that the intent of the authors was NOT including Diffusers as "bodywork"
It does say "any attached component" so its easy to say this includes the Diffuser, but the word Diffuser does not appear anywhere in the paragraph. Thats very odd being the diffuser is such a critical part of the performance of the car.
9.1.1.4.d
It's clear this is where the authors address the Diffuser and cover ALL three dimensions of it. Hight, Width & Length.
Re-reding both sections makes me think they had no intention of ever referring to a Diffuser as "Bodywork"
Its there another place in the GCR that makes the connection between the two ?
Rob Nicholas
Rob,
I swear we have hed this discussion many times over the years.
I think of the diffuser as an aero device. Others think of it as bodywork.
9.1.1.4.c is basically a rule written for FF that folks have interpreted into FC.
It sort of makes sense as a rule for a non-wing class. I have always thought it left some to be desired when applied to FC.
Obviously at the 2006 Topeka Runoffs, Niki's FC car with 14 different aero elements seemed to be treated as legal.Even DaveW had another front wing mounted on his front shock cover. Go figure...
No, we did not intend that. Diffusers are and always have been considered bodywork - no different than any other undertray-type component - and are described as such.
Wrong again.9.1.1.4.d
It's clear this is where the authors address the Diffuser and cover ALL three dimensions of it. Hight, Width & Length.
Re-reading both sections makes me think they had no intention of ever referring to a Diffuser as "Bodywork"
Try the very first sentence in the Bodywork rules:Its there another place in the GCR that makes the connection between the two ?
9.1.1.4. Bodywork
For the purposes of this section, bodywork includes all panels external to the chassis/frame and licked directly by the air stream. This includes panels above or below the floor pan, and the bottoms of any side pods.
Even if that class-specific description had not been inserted, you always have the Glossary definition that would take precedence, even if the wording is way over-inclusive.
R. Pare
Keep in mind I'm just asking, I'm not trying to promote any changes to the rule, just asking why the wording is so bad on such a critical component of an FC.
You used the word "WE" so is it safe to assume you & others purposely left out the word Diffuser wile trying to define its overall shape ?
Mike E
You are correct, we ask all the time about the Diffuser. Your name is at the top of the tread so I'm assuming you started this because you are flip flopping on the Diffuser rule ? Is that a fair statement ?
Rob Nicholas
Rob,
I live in Florida, flip-flops are standard year round.
I started the thread to better understand the current GCR position.
Yes, I am developing what the F2kCS position will be for 2013.
At this point in the discussion i think the "non-widening behind the rear axle" rule should not apply to F2000.
a. it is difficult to enforce.
b. it restricts development in what is a "development" class.
I do think the non-widening rule needs to stay in the F1600 rule set.
Rear Wing End Plates
Not mentioned so far in this discussion is that numerous rear wing end plates have some sculpting, venting, and/or a wicker type arrangement on the trailing edge. If someone is picky about the measuring of these, many rear wing end plates are illegal - ie. at some point these get wider in the horizontal plane. (I'm assuming the end plates are considered bodywork, not part of the wings).
I liked the F2kCS interpretation - if it fits in the box, its legal.
Francis Kennette
At least 1/2 of all F2000 rear wing endplates get wider at the rear. But, rear wings as aero devices are considered wings.
Diffusers, as aero devices, are considered bodywork.
No confusion at all.
Rob,
I live in Florida, flip-flops are standard year round.
I started the thread to better understand the current GCR position.
Yes, I am developing what the F2kCS position will be for 2013.
At this point in the discussion i think the "non-widening behind the rear axle" rule should not apply to F2000.
a. it is difficult to enforce.
b. it restricts development in what is a "development" class.
I do think the non-widening rule needs to stay in the F1600 rule set.
Mike, as always thanks for your input and response!
That helps a bunch in getting the car prepared.
Now me & Kevin can get back to debating what parts to bolt on.........
Rob,
I can guess which parts Stan and Rennie want you to bolt on.
The reason i think the "widening rule" is good for F1600 is that i can envision a whaletail body that is 95cm wide and ~95cm behind the rear axle creating a ton of downforce. Think ADF or DB1, Eagle long tails.
From Frog's post:
"But, rear wings as aero devices are considered wings.
Diffusers, as aero devices, are considered bodywork."
So if a rear wing end plate attaches to both the diffuser and the wing, (which many do, especially with the larger diffusers) which is it? This entire conversation wouldn't be necessary if the powers that be would say for FC/F2000 "if it's under 95cm wide, it's okay".
FK
I meant the class as a whole, regardless of series.Well, then you could race USF where they just tell you what exactly what diffuser to use and charge you an arm and a leg for the privilege... think of it as a convenience charge for removing the headache of having to think
It seems to be non stop constant squabbling over the rules these days. Its really annoying, and seems to do nothing to improve the class or the racing.
it reminds me of the uber productive FA meetings, and we know what those accomplished.
Awww, come on guys, it's so simple. Maybe you need a refresher course. Hey! It's all ball bearings nowadays.
Nah...as I said earlier we've moved on from the design that folks complained about.
Stan Clayton
Stohr Cars
That rule has bee around forever, and has always pertained to FC as well as FF (there was nothing in the old rules that over rode that authority as applies to FC), yet it has never been enforced against FC diffusers for whatever reason. I wanted to get rid of it after Frog brought it up last year, but apparently the rest of whomever that had the authority ( Crb and ?) for the finalized version didn't, so it stayed in. Since diffusers are a defacto part of FC designs, it might be easiest to just have an insert saying the diffusers are not subject to that rule.
Sorry, but I don't understand just what you are referring to.You used the word "WE" so is it safe to assume you & others purposely left out the word Diffuser wile trying to define its overall shape ?
Rob Nicholas
Looks like the CRB has solved this problem for us. As of 4/1/2013 there will be no prohibition on bodywork increasing in width behind the rear axle centerline.
I disagree
Rob,
I live in Florida, flip-flops are standard year round.
I started the thread to better understand the current GCR position.
Yes, I am developing what the F2kCS position will be for 2013.
At this point in the discussion i think the "non-widening behind the rear axle" rule should not apply to F2000.
a. it is difficult to enforce.
b. it restricts development in what is a "development" class.
I do think the non-widening rule needs to stay in the F1600 rule set.
Frog:
I'm not sure how you can call FC a development class. It's teetering on a vintage spec class IMHO.
Jimmy
Jimmy Hanrahan
jimh3063@yahoo.com
The powers-to-be saw it my way and have eliminated the "bodywork widening behind axle" rule.
FF
FROGGY... So does that mean we can put 16" diffusers on FF's now.. They fall under the same basic rules, just their reference plane is a little longer (rear of rear wheels).. So aft of the rear wheels we could actually have a diffuser type element.. 9.1.1.6 i, no more than 16" wide
9.1.1.5. Control of Undersides Shaping (page 261)
It is the intent of these rules to minimize (not eliminate) the use of “ground effects.”
a. A reference area is defined
Formula F: by the full width of the lowest surfaces of the car licked by the air stream between the front bulkhead as described in B.3.a above and the rear of the rear tires.
9.1.1.6
b & i Looks like an FF can have a 16" wide diffuser ..
9.1.1.6.j. (FC only) Diffuser undertrays, to the maximum allowed bodywork width are permitted, but any portion within the reference area (B.5) must comply with the reference area measurement rules.
Interesting read...
-Bob
Stan,
What car was in that picture you referenced? Got a full side shot?
Ken
Bob,
Keep in mind 9.1.1.B.5.a which controls the area from the front bulkhead to the rear of the rear tires. 9.1.1.B.4.d which defines the overhang of undertrays/diffusers; and 9.1.1.B.6.i which prohibits down-turned fences or strakes on the body in FF.
That is Mike Manning's RF-00 Pinto-powered FC with our front and rear wings and diffuser. I have numerous photos of the car, but unfortunately not a full side shot. Is there anything I can send you? Stan
Stan Clayton
Stohr Cars
No, for some reason it looked like a different or new car. I thought you maybe were holding something back and where about to spring a new car on us.
Ken
I am, but this car isn't it...
Stan Clayton
Stohr Cars
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