Possible for a 1.6 to be competitive in PTF/TTF with manly driving?
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Just to ad to this... I did a very silly thing and ran skinny little STREET tires size 175s so I could downclass my 95 1.8 Spec Miata to be in PTF to get the PTF regional points for a weekend. It was horrible and I won't be doing that again unless it was the only way I could get points for my class. The problem with the little 175s was braking and cornering (pretty much what you need tires most for). I had to play this timid braking game to be able to actually stop and the turns.. well, it made my Miata feel more like a Mustang (haha). I was 10 to 12 seconds off the pace of properly tired Toyo RR 205 spec miatas. I did have lots of point and laughs as I did the weekend on donuts though!
Funny little side story though... Once upon a time there was this guy with a 2003 Miata who 'downclassed' to TTF with his tire size and he (at one time) held almost all the TTF records for the Midwest and Great Lakes regions but a 4 door FWD Infiniti G20 sedan got rid of almost all his records (usually by 5 to 7 seconds actually). His only 'standing' record right now in TTF is a track NASA Midwest has not returned to (and will not return to I'm told) so we simply didn't get the opportunity to take away that record... lol
Funny little side story though... Once upon a time there was this guy with a 2003 Miata who 'downclassed' to TTF with his tire size and he (at one time) held almost all the TTF records for the Midwest and Great Lakes regions but a 4 door FWD Infiniti G20 sedan got rid of almost all his records (usually by 5 to 7 seconds actually). His only 'standing' record right now in TTF is a track NASA Midwest has not returned to (and will not return to I'm told) so we simply didn't get the opportunity to take away that record... lol
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^ It is pretty simple. You get points back (subtract points) when you downgrade the tire size and using a street tire means no + points. Needless to say, you get a lot of points to subtract using 175s
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http://www.nasaproracing.com/rules/p...ring_rules.pdf
Tire width points assessed or points credited are determined by the difference between the
width of the largest tire on the vehicle and the assigned base tire size as follows:
Equal to or greater than: 10mm +1, 20mm +4, 30mm +7, 40mm +10, 50mm +13,
60mm +16, 70mm +19, 80mm +22, 90mm +25, 100mm +28, 110mm +31, 120mm +34, etc.
Equal to or less than: -10mm -1, -20mm -4, -30mm -7, -40mm -10, -50mm -13, -60mm -16,
-70mm -19, -80mm -22, -90mm -25, -100mm -28, -110mm -31, -120mm -34, etc.
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^ Incorrect. You might want to read the PT rules again and take a look at the top of page 18 where it clearly talks about tire points. (including how you can add or subtract points)
http://www.nasaproracing.com/rules/p...ring_rules.pdf
Tire width points assessed or points credited are determined by the difference between the
width of the largest tire on the vehicle and the assigned base tire size as follows:
Equal to or greater than: 10mm +1, 20mm +4, 30mm +7, 40mm +10, 50mm +13,
60mm +16, 70mm +19, 80mm +22, 90mm +25, 100mm +28, 110mm +31, 120mm +34, etc.
Equal to or less than: -10mm -1, -20mm -4, -30mm -7, -40mm -10, -50mm -13, -60mm -16,
-70mm -19, -80mm -22, -90mm -25, -100mm -28, -110mm -31, -120mm -34, etc.
http://www.nasaproracing.com/rules/p...ring_rules.pdf
Tire width points assessed or points credited are determined by the difference between the
width of the largest tire on the vehicle and the assigned base tire size as follows:
Equal to or greater than: 10mm +1, 20mm +4, 30mm +7, 40mm +10, 50mm +13,
60mm +16, 70mm +19, 80mm +22, 90mm +25, 100mm +28, 110mm +31, 120mm +34, etc.
Equal to or less than: -10mm -1, -20mm -4, -30mm -7, -40mm -10, -50mm -13, -60mm -16,
-70mm -19, -80mm -22, -90mm -25, -100mm -28, -110mm -31, -120mm -34, etc.
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Keep in mind the skinnier tires typically won't help you anyway (they certainly showed me how ill-handling a Miata can be being so far off the pace!)
I can assure you the miata on 175 street tires was far from competitive in PTF (and not much fun to drive either)
I can assure you the miata on 175 street tires was far from competitive in PTF (and not much fun to drive either)
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^ Incorrect. You might want to read the PT rules again and take a look at the top of page 18 where it clearly talks about tire points. (including how you can add or subtract points)
Keep in mind the skinnier tires typically won't help you anyway (they certainly showed me how ill-handling a Miata can be being so far off the pace!)
http://www.nasaproracing.com/rules/p...ring_rules.pdf
Keep in mind the skinnier tires typically won't help you anyway (they certainly showed me how ill-handling a Miata can be being so far off the pace!)
http://www.nasaproracing.com/rules/p...ring_rules.pdf
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Trust me when I say that I'm well versed in the PT rulebook. I'm quite aware of the way tire points work, but what I'm saying is that I don't you can't drop below your base class by running a skinny tire. If a 1.6L PTF** Miata were to run a 205mm wire, he would get 1 point back, but if a 1.8L PTE Miata were to run a 225mm wide tire, I strongly doubt Greg would allow it to run PTF as a 19pt car.
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seems like a lot of testosterone here boys
FYI Tidbit: That 2003 Miata I told you about that 'downclassed' to F class by tire size participated at NASA Nationals with that car in the past (2 different years actually I believe but I'd have to look it up to make sure) <-- It was as a TTF car though (not PTF)
Edit: ...just checked (looked it up)
Bill participated at NASA Nationals in TTF with his 2003 Miata back in 2006 and 2007 (he was also the TT Group Leader for NASA Greatlakes and Midwest at that time IIRC)
FYI Tidbit: That 2003 Miata I told you about that 'downclassed' to F class by tire size participated at NASA Nationals with that car in the past (2 different years actually I believe but I'd have to look it up to make sure) <-- It was as a TTF car though (not PTF)
Edit: ...just checked (looked it up)
Bill participated at NASA Nationals in TTF with his 2003 Miata back in 2006 and 2007 (he was also the TT Group Leader for NASA Greatlakes and Midwest at that time IIRC)
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..and um guys, you might want to take a look at what Greg himself said about it:
"It is permitted, and rarely happens. You must still be compliant with the limit on Adjusted Wt/Hp ratio for that class. Since the only credit points are for tire size, it means that you are running on smaller tires, probably street tires, and have little or no mods to the vehicle otherwise."
nasaforums.com • View topic - UP-classing (or down?)
"It is permitted, and rarely happens. You must still be compliant with the limit on Adjusted Wt/Hp ratio for that class. Since the only credit points are for tire size, it means that you are running on smaller tires, probably street tires, and have little or no mods to the vehicle otherwise."
nasaforums.com • View topic - UP-classing (or down?)
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..and um guys, you might want to take a look at what Greg himself said about it:
"It is permitted, and rarely happens. You must still be compliant with the limit on Adjusted Wt/Hp ratio for that class. Since the only credit points are for tire size, it means that you are running on smaller tires, probably street tires, and have little or no mods to the vehicle otherwise."
nasaforums.com • View topic - UP-classing (or down?)
"It is permitted, and rarely happens. You must still be compliant with the limit on Adjusted Wt/Hp ratio for that class. Since the only credit points are for tire size, it means that you are running on smaller tires, probably street tires, and have little or no mods to the vehicle otherwise."
nasaforums.com • View topic - UP-classing (or down?)
#39
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For MIDO-->
1995 Infiniti G20 at 2011 NASA Nationals set the new TTF track record with a 1:46.345
Meanwhile, in 2012, the PTF track record (and 2nd place finisher) was (1:47.130) for PTF by Walter Carlos in an Rx7 (g20 was 1st place but slower lap time)
Meanwhile, SM fastest lap time in 2012 at MidO was a 1:43 and PTE was 1:41.684 in a Honda CRX
^ bottom line is I highly doubt a PTF/TTF Miata will be as competitive