Region: 33 SFR
Year : 1991 Posts: 167
Status: Offline
posted
I am bringing up this thread to ask a simple of, "do you want a clearer rule written to replace rule 9.1.8.C.1.k.1.a "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."
What about this proposal?
"1.6L cars may replace the stock air box up to the MAF sensor with any air filter and adapting assembly. The adapting assembly must be straight and attach to all four mounting screws on the MAF sensor with the other end fully enclosed by an air filter element. The adapting assembly can be of any rigid material type with a single wall thickness without air gaps, length and diameter are unrestricted, but it may not extend through any opening to outside of the engine bay. A single heat shield can be added but cannot be larger 144 square surface inches and can only be attached to the adapting assembly in two places.”
I am proposing this because I am building my Spec Miata as my College Senior project and want a better defined rule here so I know what I can build. I have some crazy ideas that I want to try as they fit the current rule I think, but re-writing the rule to what I have above will narrow down what I am have in mind.
-------------------- Joshua Fine SCCA member 323214 since 2003 Novice Permit in 2010 Racing 2011
Region: SFR / NorCal
Car #: 72
Year : 93 Posts: 1276
Status: Offline
posted
The NASA rule:
12.2 Air Filter
1600cc engine powered vehicles may use a cone-type air filter assembly. The air filter assembly may include integrated or attached components that may serve the purpose of shielding ONLY the air filtration element and air intake tube prior to the AFM from radiant engine heat. Any pieces attached to the air filtration element or intake tube may extend no further than 1.5 inches in any direction from the filtration element or from the air passage within the intake tube and may not shield, overlap or protect the AFM itself from engine heat.
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.
------------- Addresses the filter and "shielding" but doesn't say much about the intake tube itself.
-------------------- NASA Nor Cal SM series Director www.molaps.com
Winner - Ford Racing Mustang Challenge Driver Shootout
Evil Genius Racing / Race Engineering / Stewart Development
Region: CFR
Car #: 97
Year : 1990/99 Posts: 788
Status: Offline
posted
quote:Originally posted by SCCA_Racer: I am bringing up this thread to ask a simple of, "do you want a clearer rule written to replace rule 9.1.8.C.1.k.1.a "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."
What about this proposal?
"1.6L cars may replace the stock air box up to the MAF sensor with any air filter and adapting assembly. The adapting assembly must be straight and attach to all four mounting screws on the MAF sensor with the other end fully enclosed by an air filter element. The adapting assembly can be of any rigid material type with a single wall thickness without air gaps, length and diameter are unrestricted, but it may not extend through any opening to outside of the engine bay. A single heat shield can be added but cannot be larger 144 square surface inches and can only be attached to the adapting assembly in two places.”
I am proposing this because I am building my Spec Miata as my College Senior project and want a better defined rule here so I know what I can build. I have some crazy ideas that I want to try as they fit the current rule I think, but re-writing the rule to what I have above will narrow down what I am have in mind.
The rule is fine as written. Baffles and the like are already addressed. Also if a rule were written requiring a straight tube than that would outlaw the older racing beats that some drivers still use. Believe me we have tried or seen many different types of intakes that were and were not legal. Some of them would amaze many on this board. The one I like the best is the cold air intake that actually circulated cool shirt water through it. I think tech might have a problem with that one!
-------------------- 2010 ARRC Champion 2010 CFR Champion 2010 instigator of the year 2010/2011 Andrew Von C Wingman
Region: 33 SFR
Year : 1991 Posts: 167
Status: Offline
posted
Ok so I like the idea of the NASA rule but like it was mentioned it does not say anything about the tube length, diameter or bends. In my opinion, a bent tube is a baffle as it deflects the air, so that is my reasoning for eliminating the Racing Beat Unit. Without setting some sort of limitation on the intake tube itself, I think it leaves to rule to open for interpretation. I want the intake filter replacement to still be available to all competitors but proved a little more detail on what is allowed. Johnny just use the AFF fire system with one nozzle and put in a regulator, so you can discharge it onto the intake during a race and you now have a butchered interpretation of the rule providing intake cooling.
-------------------- Joshua Fine SCCA member 323214 since 2003 Novice Permit in 2010 Racing 2011
Region: Houston; SWDIV
Car #: 15
Year : 99 Posts: 680
Status: Offline
posted
quote:Originally posted by SCCA_Racer: Ok so I like the idea of the NASA rule but like it was mentioned it does not say anything about the tube length, diameter or bends. In my opinion, a bent tube is a baffle as it deflects the air, so that is my reasoning for eliminating the Racing Beat Unit. Without setting some sort of limitation on the intake tube itself, I think it leaves to rule to open for interpretation. I want the intake filter replacement to still be available to all competitors but proved a little more detail on what is allowed. Johnny just use the AFF fire system with one nozzle and put in a regulator, so you can discharge it onto the intake during a race and you now have a butchered interpretation of the rule providing intake cooling.
A rule will not be approved that disallows a unit presently permitted, so you can give up on that. Personally, I don't think you'll get anywhere, but if you got time to kill.......
-------------------- James York
sponsored by: Stan's Auto Center, Lafayette LA powered by: East Street Racing, Memphis TN set up guru: Gilfus Racing, Austin TX
quote:Originally posted by Gatoratty: 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.
Two quick thoughts for what it's worth... which isn't much.
1. My interpretation of the rule would be that only a cone style air filter is legal. To me, that means an air filter attached to the AFM w/o any type of tube. Also, "cone" can be very vague.
2. Since it is given that there can be a tube between the AFM and air filter, then there is lots of room for creativity. I've got an intake tube that runs from the AFM past the steering shaft, down through the opening next to the wheel housing to near the rear of the LF wheel, with a cone filter at the end. There is no 'ducting or baffling of air to the air filter', it's simply pulling the air that is around it, just like all the units. Run with an air pressure sensor on the track, find the best spot, and mount your air filter. My opinion... perfectly legal.
How about mounting a small brake duct fan inside the tube between the AFM and the cone style air filter. Two wires. Ground to the tube itself, power wire coming out the bottom and wired to the A/C so the driver could switch his 'ram air' on and off. OK... this one is a stretch. Besides, it doesn't make much of a difference... at least that's what I've been told.
-------------------- "I've got 5 kids... here there are hundreds"
Region: 33 SFR
Year : 1991 Posts: 167
Status: Offline
posted
Legal on a 1.6L but not on a 1.8L from my last read through the rules. Anything you can bolt onto the 1.6L MAF not ducting air and slap a cone filter on it and you are good to go.
-------------------- Joshua Fine SCCA member 323214 since 2003 Novice Permit in 2010 Racing 2011