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PostPosted: February 13, 2009, 5:03 am 
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I agree that the NASA class system is a bit confusing when you first see it from the outside. But then I think the SCCA classing is just as confusing when you first see it.

With NASA (for our purposes here) there are really two basic class progressions. The ST2, ST1, SU progression and the TT/PT progression. TT (time trials) and PT (performance touring) are really one long class scale based on expected power to weight and modification points; but broken up into smaller groups; TTF/PTF through TTA/PTA with TTR/PTR/TTU/PTU on top as the wide open classes. TT is essentially full track AutoX with traffic & unlimited passing - but lap count & position doesn't matter - just your fastest lap in a session. This does lead to some odd on-track behavior - particularly when you have some people on hot laps and others cooling tires & looking for open track so they can put in a hot lap. PT uses the same construction rules, points & classes as TT but for full on racing classes. The idea is that you can build a TT car and just move to racing in PT when you are ready.

The ST rules are completely separate from the TT/PT rules except where the general club rules (the CCR) dictates common ground. However the ST rules allow significantly more modification that the TT/PT rules do. A car built to compete in an ST class would probably be classed in TTU or TTR (depending on tires) if it was used for time trials. Exceptions to this are cars that are defined in the TT/PT rules with a base class & points, and have only been modified in such a way that the changes could be clearly accounted for in the TT/PT rules package. I have not looked into the TT/PT rules to see if any seven variants are classed.

Regarding the points for aero mods in ST, it may be possible to have those rules tweaked a bit where the aero penalty would be reduced. It would just take time & data to show the rule was excessive when it came to performance in class. Considering how badly high speed drag hurts low horsepower cars I think we would be able to build a case eventually.

I know all of this is pretty basic but I wanted to cover this in case anyone new to the racing environment was trying to figure out what the heck we are all talking about.

The real benefit to all of this is that we can build either traditional locosts or middies and still end up on the track with a place to race our cars. If we can all agree on common specifics within the ST rules package then we have a framework for a private sub-class that could potentially grow into our own recognized class. For us middy fans the big disadvantage might be that we end up racing in SU where we are uncompetitive while traditional (non aero) locosts could be built and classed competitively in ST2. Even a very lightweight middy built to fit ST2 specs would likely get hammered in SU.

Personally I think building to ST2 specs would be a great way to limit ourselves and at the same time allow a fair amount of freedom to build what and how we want. Thoughts?

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PostPosted: February 13, 2009, 5:07 am 
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Blackbird wrote:
Erioshi, your build plan is pretty much what I'm building, I think it'll make for a good competitive car.
I'm not sure how you're going to get to 1100 lbs with the driver in full race trim though (cage, fuel cell, fire sys etc..).

It was a number I pulled out as an example. While I would like to be that light, the reality is that I will end up heavier.

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PostPosted: February 13, 2009, 8:25 am 
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You guys are both right! Seems doable, probably not by me though. :)

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PostPosted: February 13, 2009, 8:29 am 
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Erioshi, thanks that was a helpful explainer for me..

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PostPosted: February 13, 2009, 11:19 am 
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erioshi wrote:
The ST rules are completely separate from the TT/PT rules except where the general club rules (the CCR) dictates common ground. However the ST rules allow significantly more modification that the TT/PT rules do. A car built to compete in an ST class would probably be classed in TTU or TTR (depending on tires) if it was used for time trials. Exceptions to this are cars that are defined in the TT/PT rules with a base class & points, and have only been modified in such a way that the changes could be clearly accounted for in the TT/PT rules package. I have not looked into the TT/PT rules to see if any seven variants are classed.

Not to be rude, but you still seem a little confused on the specifics of the rules structure too...For our purposes here PT/TT A-H isn't any more applicable than American Iron or Spec Miata. A Locost will never fall into an PT/TT A-H class. So really there is currrently only 1 progression of classes for us. There is also no such class as PTU or PTR, unless you are talking about ST1 and SU. If you read both sets of rules, you'll quickly note that the the TTS/U/R rules are almost verbatim the ST2/1/SU rules. Using the same power to weight, the same adjustment factors, and the same list of approved non-production and tube frame cars. For all intents and purposes, and especially for this discussion, any car build to TTS/U/R class rules is an equivalent ST2/1/SU class legal car, with the exception of the mandated vehicle/driver safety requirements between the HPDE rules and Competition rules in the CCR. And any ST class car will be certainly be legal in the directly equivalent TT class.

You are however spot on with your explanation of how the TTS/U/R events compete differently than the ST2/1/SU events...And with the fact that ST2 would probably be the best basis for a fast and reasonably affordable class try to race Locost type cars in. Of course that may change if/when the "tube frame only" classes/rules are put in place.

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PostPosted: February 13, 2009, 3:13 pm 
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Fair enough! I haven't compared the ST and PT/TT rules back to back recently. The last time I looked closely at those rules it was from the perspective of competing in TT and planning a new TT/PT build. Eventually I decided the track car I had on hand couldn't be made competitive in PT and I didn't want to cut up my Evo so I scrapped the idea until I could find a better solution to go door to door.

The whole reason I tossed in the PT/TT stuff is for background information. For anyone just coming into all of this a fairly natural progression is HPDE then Time Trials and finally full on racing. My point was the transition from TT to ST (as I recalled it) might not be as smooth as it was for some of the other classes. The good news is that it looks like I'm wrong.

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PostPosted: June 3, 2009, 4:37 am 
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An update with some new info copied from my post here: http://www.locostusa.com/forums/viewtopic.php?f=18&t=6715&p=68767#p68767

erioshi wrote:
The official NASA website is here: http://nasaproracing.com

The class rules are available here:http://www.nasaproracing.com/rules/Super-Touring.pdf

And there's a brief discussion about them on this forum here: http://www.locostusa.com/forums/viewtopic.php?f=38&t=6327

The NASA ST/SU forums are here: http://www.nasaforums.com/viewforum.php?f=18&sid=90bc04403f32e02246a86577d47599e2
And a thread introducing the class is here: http://www.nasaforums.com/viewtopic.php?f=18&t=26396

Per Greg Greenbaum, NASA's Director of ST/SU:
Greg Greenbaum via the NASA Forums wrote:
The "purpose" of the STR classes is to allow a lot of tube-frame cars running with other organizations to now also run with NASA. In addition, you now have two different classes you can run with in NASA (ie, Supersize at the Championships for two Championship races instead of one).

My concern is that a car based on a street vehicle (from a body & aero perspective) could be at a serious disadvantage when confronted with purpose built, single seat sports racers built to the same rules package. It's also worth noting that NASA's aero rules for STR & SU seem to be completely unlimited at this point.

One possibility might be to attempt to become ST classified and just pay a penalty on the car's power to weight ratio. The ST classification rules do list that kit cars may be granted an exception so you might be able to get the LaBalla classed with a mod factor that way. The ST aero rules are still very open but there is one restriction:
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2) ST1 and ST2 only (not applicable for STR1 and STR2): Aerodynamic modifications are unrestricted, except that a rear wing (or rear spoiler for wagon-style bodies), may not exceed a height of eight (8) inches above the roofline (or OEM windshield height for convertibles).

And here's more from general info from the ST/SU rules:
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7.1.1 ST1 & ST2

Any closed wheel/fendered production vehicle, approved for street use by the D.O.T., T.U.V., or Japanese government, that complies with all NASA safety requirements in the CCR, and all of the restrictions and limitations listed below in 7.2 and 7.3 is eligible to compete based on the “Adjusted” weight/power ratios below:

Super Touring 1 (ST1) = “Adjusted” wt/hp ratio equal to, or greater than, 5.50:1
Super Touring 2 (ST2) = “Adjusted” wt/hp ratio equal to, or greater than, 8.70:1

Performance enhancing modifications are otherwise unlimited. Some kit cars and purpose-built tube-frame or monocoque racecars may be permitted to compete in ST1 and ST2 with the approval of the NASA National Super Touring Director as they present for competition. The National ST Director will determine and publish any additional modification factor(s) for the Adjusted weight/horsepower ratio for those vehicles, as well as any other specific limitations and restrictions placed on those vehicles. Note, the addition of the STR1 and STR2 classes in February of 2009 does not negate or repeal the previous (or future) approvals of the tube-frame and non-production vehicles for ST1 and ST2 listed in Section 8. All of these approvals will be valid at least through the end of the 2009 season. Many (and possibly all) of them, will continue to be valid through the 2010 season and beyond.

7.1.2 STR1 & STR2

Any closed wheel/fendered racecar, that complies with all NASA safety requirements in the CCR, and all of the applicable restrictions and limitations listed below in 7.2 and 7.3 is eligible to compete based on the “Adjusted” weight/power ratios below:

Super Touring R1 (STR1) = “Adjusted” wt/hp ratio equal to, or greater than, 5.50:1
Super Touring R2 (STR2) = “Adjusted” wt/hp ratio equal to, or greater than, 8.70:1

Performance enhancing and chassis/body/aero modifications are otherwise unlimited.

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PostPosted: June 3, 2009, 4:43 am 
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Also it looks like NASA is making the use of GPS accelerometers official as part of the rules compliance tool kit. From the latest ST/SU rules:
Quote:
10.2 Vehicle Inspection

All completed ST Car Classification Forms will be available from the ST Director (or Race Director if there is no Regional ST Director) for review by any competing driver by request. Super Touring vehicles are subject to detailed inspection by any NASA Technical Inspector and visual inspection by Super Touring competitors at any time when the car is at the track or at prearranged mutually agreed upon times when the car is not at the track. Super Touring Directors retain the right to request any disassembly or other procedure required to verify vehicle compliance. At random times or at the discretion of the Super Touring Series Directors, any car may be ordered to report for rules compliance on a chassis dynamometer. All official Super Touring dynamometer tests will be open. All Super Touring competitors have the option to be present for official chassis dynamometer testing. As well, competitors may have GPS accelerometers placed in/on their vehicles at any time by Super Touring Officials to help verify rules compliance. (Note: It is likely that AWD vehicles will be required to have continuous GPS monitoring at the NASA Championships. The current approved units are the MaxQData MQGPS and MQ200 series.)

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PostPosted: June 3, 2009, 12:14 pm 
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The new STR classes look like a fun place to race a Locost without having to worry about many rules.

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PostPosted: June 3, 2009, 12:34 pm 
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I don't know...To me STR looks like a fun place to race, as long as you're building a car with massive tunnels like the old GTP cars. Maybe at first you won't need that to be competitive, but if/when the class ever starts to catch on then it will quickly turn into amateur GTP...Be it for better, or worse. I'd much rather try to run competitively in ST2 with a Locost where I believe it would be most competitive in the long run, regardless of whether it's a non-aero car with a power-to-weight advantage or it utilizes the same open rules aero-modifications as it could in STR just with a power-to-weight disadvantage.

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PostPosted: June 3, 2009, 1:06 pm 
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A competitive locost for ST2 and STR2 are two different cars.

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PostPosted: June 3, 2009, 2:22 pm 
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Other than the allowed power-to-weight ratio, what are the differences between an "aero-mods" ST2 competitive Locost and a STR2 competitive Locost??...As far as I know there is absolutely no definition or limitations on what the term "aero-mods" allows, so as long as its appearances are still identifiable as a Lotus 7-esqe.

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PostPosted: June 3, 2009, 2:30 pm 
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I don't think that an aero modded locost can be competitive at all in ST2, therefore it'll be very different than an aero modded locost that can be built for STR2.
Also, ST2 legal car in definition will be a replica of the Lotus / Caterham / Locost 7, while STR2 is a catch class for tube frame vehicles therefore I'd imagine that one could stretch the definition much further.

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PostPosted: June 3, 2009, 3:54 pm 
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Yes one could strech the design constraints much further in STR2 because there is no make/model restrictions, but then it really wouldn't bear much/any resemblance to a "Lotus 7 replica" anymore either. There isn't that much more you could do to it and still call it a "Lotus 7 replica" than the rather open ST2 rules currently allow, other than essentially sticking a Lotus 7-ish looking nosecone on a Formula/Sports Racer chassis. Remember that ST2 specifically states that "Aero modifications are unrestricted". I just don't see how that wording prevents aerodynamic modifications to a "Lotus 7 replica" being added, that are similar in appearance to those that are seen on the Donkervoort racer. When they chose to add the wording "aero-mods" to the Lotus 7 replica line, they must have had some idea of wide ranging possibilities that would be allowed. Otherwise they wouldn't have given it the power-to-weight hit that they did. So given the current wording, what specifically would actually prevent an aero-mod Locost from being competitive against the cars in ST2 compared to the completely unrestricted design cars in STR2? Sure it has a lower power limit at the same weight, but has similar "unrestricted" aero mods and it's competing against very downforce limited (by design not rules) cars...And we all know how significant of an advantage that downforce can be in road racing. I just don't see any justification that a Locost modified for significant improvements in drag and downforce couldn't be just as, if not more, competitive in ST2 than a non-aero-mod Locost.

I should clarify: I'm not saying that an aero Locost will definitely be the most competitive way to build a Locost for ST2, but that since nobody has tried building one to the limits of the rules yet who's to say that it also couldn't. I do firmly believe however that as soon as some well designed from the ground-up single seat racecars start running in STR2, that anything based significantly on a Locost chassis/body will likely be in way over its head.

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Last edited by Driven5 on June 3, 2009, 4:30 pm, edited 2 times in total.

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PostPosted: June 3, 2009, 4:20 pm 
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STR2: Black Brick anyone ?


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