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PostPosted: February 21, 2015, 1:57 am 
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The voice of reason
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I'm not sure I follow. This is exactly what my suggestion is attempting to address...


Well I'm just saying I may not have the answer. Last time I looked at the T5 gears it seemed I could be above 5k RPM or maybe even 6 so I suppose I'm really in the same ballpark as many modern engines, but not Hondas, BECs or some others.

I think people will play with their engine tunings to cut their torque under 6K RPM, so their street cars will be not so streetable after all. And this won't effect the power in the RPM band they are using.

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PostPosted: February 21, 2015, 2:25 am 
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Even though my car would likely end up in such a class when it's done, after reading through the latest Yahoo group posts I don't see much reason for joining the official discussion there. I had a much longer explanation of my reasoning written out...But I'll just leave it at a lack of confidence in the brainstorming session there being capable of producing a satisfactory outcome. Which I find a bit disappointing, as brainstorming is probably one of my favorite pastimes.

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PostPosted: February 21, 2015, 2:51 am 
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There hasn't been much effort towards sorting out the rules yet... If you don't like what you see with regard to the brainstorming going on, that implies that your input would be beneficial, right? I wish this would instead motivate you to come straighten the group out.

Dean


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PostPosted: February 21, 2015, 10:42 am 
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They already seem to have a pretty good idea of what they want the class to look like and how little they want to deviate from the existing rule structure. Which is to say, not enough for me to find it appreciably more interesting than the existing DM/EM classes...Especially since that's realistically all that the "street" cars in the class will inevitably become a minor variation of anyways, if it does somehow manage to attain any level of long term success. Based on their (re)actions, they don't appear to be interested in actually brainstorming a wide variety of creative ideas for such a proposal, and I don't feel it would be appropriate to join the group just to be critical of their intended approach.


Edit:
Since there is at least one person (Dean) participating here and in that group who seems interested in seeking out and hearing what other have to say, it seems a little standoff-ish to not still share some of my other thoughts.

"Street cars" are built around fitting street car wheel and tire sizes, not pure racing (Formula Atlantic) slick tire sizes. If true street tires are uncontrollable, they should at most be running DOT-R's. In my opinion even better would be "streetable" DOT-R's...But of course my power to weight ratio will be nothing like that of the Super Stalkers that this class is pretty obviously being designed around making ideally competitive.

Continuing with an antiquated engine displacement based weight classing, even with extra adjustments for pushrod/rotary/FI/etc, just to appease the Old Guard of the SCCA means that the (lack of) cost containment and streetability of competitive engines will end up being just as exceptionally outrageous as it is in the existing classes. This is what will ensure that it remains nothing more than a class for "street legal" cars otherwise essentially built around the current DM/EM rules, rather than being a genuine home for ALL kit and homebuilt street cars like they're advertising.

I saw the 1.8x turbo multiplication factor reiterated, again without any substantiation to the notion that a 1.4x multiplication factor is inadequate. Hell, a bigger turbo yet and more boost can just as easily yield well over 2x the power of a maxed out naturally aspirated race engine of the same displacement. But the important question is whether the resultant power curve actually provides equivalency, let alone an advantage, on an autox course? I have seen no evidence, let alone proof, to support their position that the 1.4x multiplier is inadequate. Sure SCCA has further restricted turbos in DM, but my understanding is that they have done so without the engines ever having proven to be over-competitive, even with all of the money that has been thrown at the engines in that class over the years. Not making forced induction engines under-competitive is one of the few ways to actually help contain the cost of making competitive power in a displacement limited class. Going from 2.0L to 2.5L will be a substantial bump in power for the naturally aspirated engines from current DM winning power levels, but turbos will still be stuck at the same 1.4L limit which has never even been dominant in DM.

They have a chance to help cost containment before it gets out of control and is forced by politics to stay that way, but seem to prefer walking right back into the same trap as before.

In general I don't see anything in their plan that would have any chance at maintaining the genuine "street car" nature of the class at the National Championship level, any better than DM/EM. Sure the requirements may be closer to a "street car" configurations, with two symmetrically space seats, and it may be light enough of competition the first few years that true street used cars are able to win. But as soon as the first person designs and builds a car from scratch with the explicit intent of maximizing the use of each and every rule to decimate this class full of joyriders looking for a jacket, the fairy tale will be over and the (cubic-dollar) arms race will begin all over again.

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Last edited by Driven5 on February 21, 2015, 11:35 pm, edited 5 times in total.

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PostPosted: February 21, 2015, 11:19 pm 
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I don't see how a catch all class for everything home-built will work. Your only chance would be to have 2 or 3 formulas with specified powertrains, suspensions, etc but then people will be upset because their car is wider/longer/more powerful/has the wrong suspension. It seems like this concept is the only way the 750MC Locost racing series actually ends up working.

I think the bigger issue are the autocrossers that take it way too seriously. There is a reason why we're all amateurs - we're there to have fun.

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PostPosted: February 22, 2015, 11:46 pm 
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Justin - Thank you for the edit you made to your post. That's the information I was wishing for when I first read your post. I think you make good points. I don't think the class would be strong enough with Stalkers alone, but depending upon how the rules are written it does seem that an optimal design would eventually be converged upon.

Andrew may be exactly right about the great variation in cars making it difficult to achieve parity/fairness, but it seems reasonable to first get the concept in place, if possible, then divide the class up if the numbers justify. It's pretty clear that traits that will make a car more competitive will be size (smaller), power/torque (greater), and weight distribution (more central, optimally balanced front to rear, and lower) will lead to a particular design that will be best. That's OK. Someone has to win. A class that enables a multi-purpose street legal car that doesn't fit into any other class except AM, DM or EM is the objective. Having every variation in design be simultaneously optimal won't happen, of course, but at least a toy car that happens to be optimal for this autocross class could also be driven several thousand miles per year on the street and also could participate in track days.

Dean


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