Street racing threads aren't allowed because we want no part of either promoting, or justifying illegal activity. Street racing kills, and allowing the discussion means that we turn our backs on the automotive community, as well as the general population, instead of trying to set an example of the responsible and correct way to go about racing, from an enthusiast standpoint. On the street, you risk the life of not only yourself, but innocent bystanders. On the track, there's emergency medical personnel immediately available and it's a controlled environment with safety rules that are constantly reviewed and improved upon.
Now for your next issue, saying rice, or redneck are neither bigotry, nor are they racism. Granted some issues can push the bounds of stupidity, they're definitely not bigoted, or racist.
The definitions of bigot and racism are below (from Miriam-Webster's Dictionary), so we can make sure we're on the same page here, when it comes to the meaning behind those words:
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bigot
Main Entry: big·ot
Pronunciation: \ˈbi-gət\
Function: noun
Etymology: French, hypocrite, bigot
Date: 1660
: a person obstinately or intolerantly devoted to his or her own opinions and prejudices; especially : one who regards or treats the members of a group (as a racial or ethnic group) with hatred and intolerance
— big·ot·ed \-gə-təd\ adjective
— big·ot·ed·ly adverb
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racism
Main Entry: rac·ism
Pronunciation: \ˈrā-ˌsi-zəm also -ˌshi-\
Function: noun
Date: 1933
1 : a belief that race is the primary determinant of human traits and capacities and that racial differences produce an inherent superiority of a particular race
2 : racial prejudice or discrimination
— rac·ist \-sist also -shist\ noun or adjective
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So using either word you gave as an example, I'm a bit confused as to which definition rice would fall under? Rice isn't bigoted, by this definition. Doesn't appear to be racist, either. Rice comes in all races. It's a matter of personal preference, to look ridiculous enough to become classified as a "ricer," but it knows no color. It's their perogative, and not something they were born into, like they would be with their race. It might be prejudice toward the import fans, but you need to follow the definition in order for it to be either bigotry, or racism, since those single out an ethnic group.
Now using the definition of either word, what would redneck fall under? Definitely not bigot. It's another word that knows no gender, race, or color. Definitely not racism, because again, it doesn't discriminate against race. I fail to see the argument there, either.
Now had you used the word prejudice, it may have met the definition and criteria for your argument, but you didn't.
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prejudice
Main Entry: 1prej·u·dice
Pronunciation: \ˈpre-jə-dəs\
Function: noun
Etymology: Middle English, from Anglo-French, from Latin praejudicium previous judgment, damage, from prae- + judicium judgment — more at judicial
Date: 13th century
1: injury or damage resulting from some judgment or action of another in disregard of one's rights; especially : detriment to one's legal rights or claims
2 a (1): preconceived judgment or opinion (2): an adverse opinion or leaning formed without just grounds or before sufficient knowledge b: an instance of such judgment or opinion c: an irrational attitude of hostility directed against an individual, a group, a race, or their supposed characteristics
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Rice could definitely fall under that definition, as written above. Redneck, you'll still need to work on, however.