Region: Houston; SWDIV
Car #: 15
Year : 99 Posts: 680
Status: Offline
posted
Eric,
I couldn't either see or find the ad you reference, but a fabricated heat shield is not legal.
Perhaps you saw the factory heat shield?
I have seen one car actually have an AFM intake fabricated in such a way it had a heat shield built in. It was a pretty tortured interpetation of the rules I thought.
-------------------- James York
sponsored by: Stan's Auto Center, Lafayette LA powered by: East Street Racing, Memphis TN set up guru: Gilfus Racing, Austin TX
Region: NER
Car #: 09 ITA
Year : 90, 91, 94 Rentals Posts: 1109
Status: Offline
posted
I think you guys really need to open up your minds a little. If that shield (or any custom unit) is attached to the allowed (OPEN) unit, it's just part of it. The only restriction is that it can't duct air TOO the filter, says nothing about shielding from heat.
This isn't a case of 'if it doesn't say you can then you can't'...it's a case of 'if it says you can then you damn well can'.
The SP Induction intake everyone runs is totally custom remember. Add a shield to that piece and I would like to know what rule you could cite that says you would be illegal.
I am talking in concept, not about that specific shroud as I can't see where it's connected.
Region: SouthEast
Car #: 28
Year : 95 Posts: 3756
Status: Offline
posted
I disagree Andy. I think that piece is not integral to the intake at all. Just because it "touches" it shouldn't make it legal. I can be ok with an intake that has a heat reflective cover or tape or something like that but not another piece that is not integral to the intake itself.
Just seems over the line to me... Not sure how I would protest it but it seems clearly illegal to me.
It doesn't even appear to me that it IS attached to the intake anyway...
Jason
-------------------- Jason Holland Semi-interested civilian
Region: Central Florida
Car #: 3
Year : 1992 Posts: 1304
Status: Offline
posted
9.1.8. Spec Miata Class Specifications 2. 1.6L cars may replace the stock air box with a cone style air filter assembly. The air filter element is unrestricted. No ducting or baffling of air to the air filter is permitted.
I guess it will depend upon how the tech inspector and the COA interpret the definition of "cone style air filter assembly" After the fiasco at the runoffs with the COA don't expect them to be as open to interpretation in the future.
Region: MidDiv
Car #: 13
Year : 92 Posts: 2873
Status: Offline
posted
quote:Originally posted by Gatoratty: The air filter element is unrestricted. No ducting or baffling of air to the air filter is permitted.
Been thinking about this one a bit as I initially agreed with Andy's take. After a bit more thought I think the specific example above is non compliant as the heat shield looks like a baffle to me. That said, I think dry ice and or a wrap is just fine. The key word in this example is the word "baffle".
You could take it further and say that any heat shield is a baffle, but I don't think that is the case. I am cherry picking here, but a quick google finds the definition that explains why I think it is a baffle.
Baffle = a flat plate that controls or directs the flow of fluid or energy
-------------------- ---------------- Z Brothers Racing / East Street Auto
Region: CFR
Car #: 97
Year : 1990/99 Posts: 788
Status: Offline
posted
It would not consider that a baffle at all! It does not direct airflow and only serves to slow heat transfer to the intake tube. No different than mine being wrapped in tin.
-------------------- 2010 ARRC Champion 2010 CFR Champion 2010 instigator of the year 2010/2011 Andrew Von C Wingman
Region: SFR / NorCal
Car #: 72
Year : 93 Posts: 1276
Status: Offline
posted
I agree 100% with Andy. Intake and filter are open and a shield isn't forbidden unless it directs AIR (the rule doesn't say "deflects heat"). The NASA rules specifically prohibit anything that attempts to COOL the air below ambient but are silent on the prevention of the air from becoming heated above ambient. Also note the use of the words "comprised of components" when referring to the cone air filter.
12.2 Air Filter 1600cc engine powered vehicles may use a cone-type air filter. 1800cc engine powered vehicles must use the stock air filter housing. Any filter may be used, providing that it is comprised of components and materials other than air cooling systems, cooling chemicals, or cooling chemical compounds. No devices such as ducting or air deflectors are permitted to direct air to the air filter. 12.3 Definition For the purposes of Section 12.2, “cooling systems,” “cooling chemicals,” and “cooling chemical compounds” means any system or substance that enables a transfer of heat, by convection, conduction, or radiation that causes the air entering the engine to be cooler than ambient, and / or contain additional chemicals than normally found in ‘air’ as defined by the Handbook of Physics and Chemistry (CRC).
-------------------- NASA Nor Cal SM series Director www.molaps.com
Winner - Ford Racing Mustang Challenge Driver Shootout
Evil Genius Racing / Race Engineering / Stewart Development
Region: New England
Car #: 92 Posts: 1993
Status: Offline
posted
The purpose of the intake is to direct the air from the filter to the AFM.
The purpose of that heat shield is to prevent the heat from the exhaust from heating the intake air. This function is unrelated to the function of the intake itself.
What other functions can an appendage I attach to the intake serve?
-Kyle
Steve D.
Once you get past the gag reflex, the jelly ain't bad!
Region: Atlanta
Car #: 30
Year : 1999 Posts: 652
Status: Offline
posted
quote:Originally posted by pat slattery: Huge stretch in the rules, what purpose does it have other than a big heat shield?
Maybe we can attach a turbo to the intake also.
Pat
And here I thought you saved all your rational arguments for the anti-99 campaign?!?!?!
Region: SouthEast
Car #: 28
Year : 95 Posts: 3756
Status: Offline
posted
quote:Originally posted by dtfastbear: I agree 100% with Andy. Intake and filter are open and a shield isn't forbidden unless it directs AIR (the rule doesn't say "deflects heat"). The NASA rules specifically prohibit anything that attempts to COOL the air below ambient but are silent on the prevention of the air from becoming heated above ambient. Also note the use of the words "comprised of components" when referring to the cone air filter.
12.2 Air Filter 1600cc engine powered vehicles may use a cone-type air filter. 1800cc engine powered vehicles must use the stock air filter housing. Any filter may be used, providing that it is comprised of components and materials other than air cooling systems, cooling chemicals, or cooling chemical compounds. No devices such as ducting or air deflectors are permitted to direct air to the air filter. 12.3 Definition For the purposes of Section 12.2, “cooling systems,” “cooling chemicals,” and “cooling chemical compounds” means any system or substance that enables a transfer of heat, by convection, conduction, or radiation that causes the air entering the engine to be cooler than ambient, and / or contain additional chemicals than normally found in ‘air’ as defined by the Handbook of Physics and Chemistry (CRC).
Well, consider this rule tightened up this year....
don't show up with something like that to a nasa race next year...
Jason
-------------------- Jason Holland Semi-interested civilian
Region: SFR / NorCal
Car #: 72
Year : 93 Posts: 1276
Status: Offline
posted
Even as someone arguing for the legality of a heat shield that is "part of" the intake and/or air filter, I would question the heat shield that is in the picture linked above. That thing seems to be shielding the AFM, as well, which I would say IS a tortured interpretation of the rules.
I'd vote for more specificity in the rules (agree with Jason), but I'd love to see the rules allow for small shields that don't extend [much] beyond the dimensions of the intake or filter. I think the insulation in particular makes the engine provide more consistent power over the duration of a race, which I believe is empirically a good thing.
Cheers,
Dean
-------------------- NASA Nor Cal SM series Director www.molaps.com
Winner - Ford Racing Mustang Challenge Driver Shootout
Evil Genius Racing / Race Engineering / Stewart Development
Region: CenDiv
Car #: 94
Year : 90 Posts: 1319
Status: Offline
posted
Where are you measuring ambient. It's different on one side of that shield than the other.
The definition of baffle in the GCR refers to fluid. So we go to the common definition cited above. Baffle = a flat plate that controls or directs the flow of fluid or energy. That plate controls the flow of energy and air. By virtue of the fact that it is restricting airflow from the engine side of the intake, it is increasing airflow from the other side of the compartment. Thus, it is directing specific air to the intake. It doesn't have to be a directional funnel.
Imagine a wing put under the car but attached to the "free" exhaust. It would create downforce and could change the car's handling, but we'd never say that the wing is allowed.
He would have been better off chopping up the intake box and putting the cone inside the remnants. That would have made the discussion more interesting.
Region: SFR / NorCal
Car #: 72
Year : 93 Posts: 1276
Status: Offline
posted
So I would then argue that the shape of air filter itself is designed to alter the flow of air to the intake and should be illegal. Doesn't K&N invest research dollars in making a filter shape that optimizes filtration while improving flow? If K&N mass produced a cone filter that had insulation on one side, would you still call this tortured interpretation or illegal?
Is caking one side of the filter full of mud (or insulating material) illegal, since it would both a) insulate the filter on that side and b) increase flow from the other side? What if I have a big off and lots of dirt ends up on one side of the filter? Is it illegal to run again until I clean it?
Is the flat "plate" on the top of the standard K&N cone filter illegal because it restricts airflow from that direction? What if the intake was oriented such that the top of my cone filter was pointed AT the engine?
Part of the FILTER'S job is to direct airflow. I think it is impossible to argue otherwise, or there wouldn't be filters that are shaped differently or made of different materials. If the filter I design is closed on one side and open on the other, what part of OPEN FILTER does that rule violate? What alternative purpose is it serving other than to direct filtered air into the intake?
It's not so black and white. Just sayin'
-------------------- NASA Nor Cal SM series Director www.molaps.com
Winner - Ford Racing Mustang Challenge Driver Shootout
Evil Genius Racing / Race Engineering / Stewart Development
Region: Houston; SWDIV
Car #: 15
Year : 99 Posts: 680
Status: Offline
posted
quote:Originally posted by Andy Bettencourt: I think you guys really need to open up your minds a little. If that shield (or any custom unit) is attached to the allowed (OPEN) unit, it's just part of it. The only restriction is that it can't duct air TOO the filter, says nothing about shielding from heat. ....... The SP Induction intake everyone runs is totally custom remember. Add a shield to that piece and I would like to know what rule you could cite that says you would be illegal.
Easy. A heat shield can be applied directly to the intake itself and be just as effective if that was the ONLY purpose it was serving. The only reason to extend a "shield" and make it bigger and away from the item "protected" is to gain the additional benefit of impeding the flow of undesirable air. And any device which impedes, obstructs, or "baffles" air is illegal.
As a heat shield its legal, but it crosses the line when it clearly serves another purpose that is explicity prohibited in the rules.
-------------------- James York
sponsored by: Stan's Auto Center, Lafayette LA powered by: East Street Racing, Memphis TN set up guru: Gilfus Racing, Austin TX
Region: NER
Car #: 09 ITA
Year : 90, 91, 94 Rentals Posts: 1109
Status: Offline
posted
quote:Originally posted by Cajun Miata Man: Easy. A heat shield can be applied directly to the intake itself and be just as effective if that was the ONLY purpose it was serving. The only reason to extend a "shield" and make it bigger and away from the item "protected" is to gain the additional benefit of impeding the flow of undesirable air. And any device which impedes, obstructs, or "baffles" air is illegal.
As a heat shield its legal, but it crosses the line when it clearly serves another purpose that is explicity prohibited in the rules.
I was with you all the way up until the last sentence. It must baffle air TOO the intake to be illegal. And since it's not sealed, it doesn't eliminate ANY air. It's a radiant heat thing. Nothing explicitly not allowed about that. Remember the old Racing beat intake people took and turned DOWN, away from the heat? Don't limit yourself to what is available from traditional outlets.
I am asking you all to look at the LETTER of the rules, not what you THINK the intent is. Take your SPI tube, wrap it in the gold foil, attach a heat shield to it that runs any-freakin-where you want...it's legal.
And to the gentleman who made the exhaust/wing example...no go. The exhaust has enough LIMITS on it's design so that would be illegal.
Region: Houston; SWDIV
Car #: 15
Year : 99 Posts: 680
Status: Offline
posted
Andy,
Let's just say I disagree. If its keeping air away, then it's ducting cool air in. It's creating a favorable seperation toward the inlet.
Nothing about intent here, I don't subscribe to rules intent philospy.
Easy for me. If a car shows up with one at a race I attend and finishes it front of me, it will be protested the next day. If it passes, good for them, then everyone can get one and it's settled. No harm no foul. If they are tossed, and lose the sure to follow appeal to Topeka, then I get to say I told you so.
-------------------- James York
sponsored by: Stan's Auto Center, Lafayette LA powered by: East Street Racing, Memphis TN set up guru: Gilfus Racing, Austin TX
Region: NER
Car #: 09 ITA
Year : 90, 91, 94 Rentals Posts: 1109
Status: Offline
posted
quote:Originally posted by Cajun Miata Man: If a car shows up with one at a race I attend and finishes it front of me, it will be protested the next day.
Well since you have a 99, that would be impossible! LOL!
Region: MidDiv
Car #: 13
Year : 92 Posts: 2873
Status: Offline
posted
quote:Originally posted by David Dewhurst: ***Rule
No ducting or baffling of air to the air filter is permitted.***
***Baffle = a flat plate that controls or directs the flow of fluid or energy***
If we look in the GCR glossary definition we will find that the item talked about is not a baffle. "A plate or panel in a fluid container,"
As long as the item is attached to the intake "air filter assembly" it is what it is.
Wow, have to disagree on all counts. In this example air is a fluid and does behave as one. Secondly, the fluid in this case is conducting heat (energy) and the baffle impedes its flow.
Of course that assumes the stewards would listen to logic and basic physics and thermodynamics. Long shot...
-------------------- ---------------- Z Brothers Racing / East Street Auto
Region: NER
Car #: 09 ITA
Year : 90, 91, 94 Rentals Posts: 1109
Status: Offline
posted
Casey - real question. Does impeding the flow of air in turn qualify as ducting - or baffling air TO the intake under your definition? Take the temp out of it. No ADDITIONAL air is getting to the intake, no air is being directed TO the filter per the rule.
The rule says you can't direct air to the filter...nothing else IMHO.
Region: CenDiv
Car #: 94
Year : 90 Posts: 1319
Status: Offline
posted
But andy, you are directing specific air to the filter, you're just using lower air pressure, rather than a "funnel" to do it.
Imagine for example that the heat shield actually funneled away from the filter, not towards its. You would have a low pressure eddy behind it. Thus you would be directing air from the wheel well towards the intake.
Reading the rule exactly, there's nothing that says the directing of the air has to be accomplished via a funnel or baffle that's pointed at the filter. All it has to be is accomplished.
Region: NER
Car #: 09 ITA
Year : 90, 91, 94 Rentals Posts: 1109
Status: Offline
posted
I don't see it as directing air to it or away from it. Heat sheilds don't 'funnel air' in my mind. "directing air" is an 'active' term for me. A shield is a passive wall.
That is where we differ in function and definition although I understand where you are coming from.
Region: SFR / NorCal
Car #: 72
Year : 93 Posts: 1276
Status: Offline
posted
How, then, is the flat top of the filter not a baffle by your definition, Mike? If the flat rubber/plastic top of the filter is pointed towards the motor, its insulating effects would effectively cause a cooler, lower pressure point INSIDE the filter behind that "plate", drawing more air into the filter, no?
This interpretation of the shield as an air "directing" device by lowering pressure behind it seems a more tortured interpretation than what you're arguing against.
Casey, you're saying the engine compartment is a "fluid container" for air? Come on... who's stretching here?
Cheers,
Dean
-------------------- NASA Nor Cal SM series Director www.molaps.com
Winner - Ford Racing Mustang Challenge Driver Shootout
Evil Genius Racing / Race Engineering / Stewart Development
Region: MidDiv
Car #: 13
Year : 92 Posts: 2873
Status: Offline
posted
quote:Originally posted by dtfastbear: Casey, you're saying the engine compartment is a "fluid container" for air? Come on... who's stretching here?
Dean I was hoping someone would take me up on the offer. I will address Andy's point as well. That is exactly what I am saying. I would ask how you cannot see the engine compartment as a fluid container? That is what it is. It is a container that happens to have an engine and for our purposes an intake as well. For the purpose of this discussion air is a fluid and it conducts heat. Therefore the baffle rule comes into play in my thought process.
Let's assume we are arguing this with F1 guys in front of the FIA. Air is a fluid otherwise no one would go to all the trouble of CFD. And EVERYONE goes to the trouble of CFD because it does matter. That is just the fluid argument. You can still fall back on the thermodynamics argument as well due to the baffle language in the GCR rules. Of course this is just talking about it with friends. i.e. what we think really doesn't matter all that much but it is fun to think about.
Now as a more real world example, what if the heat shield/baffle on the intake some how managed to wrap around the whole motor? Is that ok? Think about a really nice insane but still connected bit of engineering. It is a heat shield and a baffle in many ways, but since it is connected to the intake it is open? I don't think so. Sometimes things just are what the are...
Hope we all realize that this is an intellectual exercise and no more. But it is fun!
-------------------- ---------------- Z Brothers Racing / East Street Auto
Region: NER
Car #: 09 ITA
Year : 90, 91, 94 Rentals Posts: 1109
Status: Offline
posted
Casey,
What if all of this 'heat protection' was done INSIDE the tube? Meaning the exhaust-side just had a molded buldge while the real intake sat inside the entire unit? Serves the same purpose yet is 100% contained inside the intake tube.
What about heat relective tape? It also does exactly what you describe as illegal - no? How about an intake that was sent to HPC? Same deal no?
If you want to fall on Thermodynamics, wouldn't you have to argue that those items are illegal as well? I might agree with you if the intake tube that attaches to the AFM was spec...but it is of open design, material, etc.
Thoughts? My point obviously is to try and point out that even the specific SHAPE of that intake tube changes the flow of air in your 'fluid container' from stock. The SPI, the RB, anything. Therefor you have to accept that piece is open and there will be some not-stock 'air baffling'. Accepting that, you now have to determine if a sheild baffles or funnels air TO the intake. I still say NO. It may change the temp of the air that is already there, but does not add air.
Region: New England
Car #: 92 Posts: 1993
Status: Offline
posted
Andy,
Are you arguing that the "heat shield" in the photo is not altering the air flow around the filter? Certainly, it does. Therefore it's illegal.
I think the easiest way to solve these kinds of debates is to take them to their extremes. With the design in the photo, that would be a sheet of metal that runs from the radiator support to the firewall separating the air filter from the engine entirely (but touches nothing except the intake tube). Would you also argue that this is legal?
The extreme of the "wrap" design would just be a very thick wrap. No matter how thick this wrap got, it would not affect the airflow to the filter.
Region: NER
Car #: 09 ITA
Year : 90, 91, 94 Rentals Posts: 1109
Status: Offline
posted
I am not arguing that it isn't altering the airflow around the filter. I am arguring that it isn't sending air TOO the filter...because THAT is what is illegal.
Again, with an open filter design and an open tube between the AFM and the filter, I fail to see how you can say that any alteration of airflow is illegal because they ALL alter the stock airflow...in very different ways. My take on the rule is that they don't want you forcing air TOWARDS the filter. It says that in the rule. A heat sheild does not do that.
Region: Ozark Mountain Region
Car #: 37, 31
Year : 96, 93 Posts: 775
Status: Offline
posted
i will not judge the intake in picture, because I can't see enough of it... But in general, I agree with Andy...
The flip side is calculate the speed the air moves throught that section... Then decide if the air is in there long enough to pick up any heat... Granted, it doesn't hurt
Region: SFR / NorCal
Car #: 72
Year : 93 Posts: 1276
Status: Offline
posted
Of course that would be illegal, Andy, because tape is just a very this ver flexible plate, right?
Casey, of course this is all just good fun. I'm on my way to Thunderhill to test out two LeMons cars today, so my creative engineering juices are flowing!
Cheers,
Dean
-------------------- NASA Nor Cal SM series Director www.molaps.com
Winner - Ford Racing Mustang Challenge Driver Shootout
Evil Genius Racing / Race Engineering / Stewart Development