sstecker Posted September 22, 2009 Share Posted September 22, 2009 not sure if so much a rule change as a discussion continued..... here is a 2600lb car using current rule set if the car was maxed out for hp/weight ratio; (if i did my excel sheet correctly) (dot and slick is max hp) class dot slick hp difference weight penalty gts 5 433 400 33.33333333 216 gts 4 305 288 16.99346405 152 gts 3 236 216 19.6969697 236 gts 2 179 162 16.81034483 268 gts 1 140 130 10.54054054 210 (i cut off after decimal to make it line up with column titles) weight penalty is instead of detuning you added ballast (swapped to slicks and added ballast) seems random. any logic behind the numbers? Quote Link to comment Share on other sites More sharing options...
jrgordonsenior Posted September 22, 2009 Share Posted September 22, 2009 Interesting differences. In my GTS3 car the weight differences is 250. 2810/255 =11.01 for Dot 3060/255 =12.00 for slicks. Quote Link to comment Share on other sites More sharing options...
sstecker Posted September 22, 2009 Author Share Posted September 22, 2009 Interesting differences. In my GTS3 car the weight differences is 250. 2810/255 =11.01 for Dot 3060/255 =12.00 for slicks. do you run slicks? do you think that is competitive? Quote Link to comment Share on other sites More sharing options...
jrgordonsenior Posted September 30, 2009 Share Posted September 30, 2009 Interesting differences. In my GTS3 car the weight differences is 250. 2810/255 =11.01 for Dot 3060/255 =12.00 for slicks. do you run slicks? do you think that is competitive? I've run slicks with other clubs at my 2800 lb. weight and yes they're faster. With the additional 250 lbs. I wouldn't even waste the tires.... Quote Link to comment Share on other sites More sharing options...
Damon in STL Posted September 30, 2009 Share Posted September 30, 2009 Last year I ran in GTS2 on Hankook 215/580R15 F200s. I bought them on closeout for $100 each and just could not pass up the deal. My e30 M3 has no way to make easy adjustments to the rear suspension....so, I left all of my suspension settings as they were for R-comps. I was told by Hankook the tires would work better with less camber than I was running....but, without the adjust ability....I ran what I had. And, because of the weight penalty for slicks....I ran 300 lbs heavy. Even with the narrower tire (I usually run a 225), older C50 compound, and the extra weight, I was very competitive. I don't have any experience running other slicks and have been told the Hankook F200s are not a "Good" slick......but, they were fast enough to win on against good competition. In one race my competition set the track record for Autobahn South and I was only about a 10th off his race time and was about a 10th faster than the record in qualifying. I'm not sure what this proves....if anything....just additional info regarding slicks. Damon in STL Quote Link to comment Share on other sites More sharing options...
sstecker Posted September 30, 2009 Author Share Posted September 30, 2009 Last year I ran in GTS2 on Hankook 215/580R15 F200s. I bought them on closeout for $100 each and just could not pass up the deal. My e30 M3 has no way to make easy adjustments to the rear suspension....so, I left all of my suspension settings as they were for R-comps. I was told by Hankook the tires would work better with less camber than I was running....but, without the adjust ability....I ran what I had. And, because of the weight penalty for slicks....I ran 300 lbs heavy. Even with the narrower tire (I usually run a 225), older C50 compound, and the extra weight, I was very competitive. I don't have any experience running other slicks and have been told the Hankook F200s are not a "Good" slick......but, they were fast enough to win on against good competition. In one race my competition set the track record for Autobahn South and I was only about a 10th off his race time and was about a 10th faster than the record in qualifying. I'm not sure what this proves....if anything....just additional info regarding slicks. Damon in STL cool thanks for that info. i would think same car performance differences would be more informational - your car with/without slicks setup for each. im trying to class my car as its between gts2 on dots and 3 on slicks. so i started running the calculations and they just didnt seem to have any logic for the penalty of slicks. when you can count the rules on one hand you would think the numbers would make sense. order of least to greatest weight penalty by % gts4 1.058823529 gts1 1.081081081 gts5 1.083333333 gts3 1.090909091 gts2 1.103448276 if slicks benefit the highest hp cars the most, why is gts5 in the middle if slicks benefit the low hp cars the most why is gts1 in 2nd, and gts 2 last Quote Link to comment Share on other sites More sharing options...
rabbit_diesel Posted October 1, 2009 Share Posted October 1, 2009 im trying to class my car as its between gts2 on dots and 3 on slicks. so i started running the calculations and they just didnt seem to have any logic for the penalty of slicks. when you can count the rules on one hand you would think the numbers would make sense. Looking at the numbers in the classing chart, it is my opinion that whoever wrote it had an idea and picked some 'nice numbers' that more or less fit the idea. Abbreviated classing chart, current version: [For clarity, this chart lists only the upper limit of each class. U has no posted upper limit. For the low limit of each class, please refer to the rules.] Class D.O.T. Slicks 5 6.000 (+ .5) 6.500 (+ 2.5) 4 8.500 (+ .5) 9.000 (+ 2.5) 3 11.000 (+ 1.0) 12.000 (+ 3.5) 2 14.500 (+ 1.5) 16.000 (+ 4.0) 1 18.500 (+ 1.5) 20.000 In the work of the author, I see a pattern. It appears he was aiming for approximately a step of 1.296, in which case the step between class #5 and #4 does not fit his pattern ---> the cut-off for #5 should have been 6.56 in order to fit his pattern. (Also, it would better fit if the cut-off for #2 was 14.3, instead.) Between D.O.T. and Slick for the several classes, the author added varying amounts. In my opinion, having added 'varying amounts' is the source of the discrepancy for the 'slick weight penalty' between the classes; the author should have used a multiplier, the same multiplier in each case. A multiplier of "1.082" has an effect similar to what appears to have been the intent of the author, and it gets rid of the difference in 'slick weight penalty' between the classes. For example: Class D.O.T. Slicks 5 6.000 (* 1.082) 6.492 4 8.500 (* 1.082) 9.197 3 11.000 (* 1.082) 11.902 2 14.500 (* 1.082) 15.689 1 18.500 (* 1.082) 20.017 Will Quote Link to comment Share on other sites More sharing options...
rabbit_diesel Posted October 8, 2009 Share Posted October 8, 2009 Looking at the current cut-offs, and modifying the outliers --> a more rational classing chart would be: [For clarity, this chart lists only the upper limit of each class. (The low limit of each class can be deduced.) (Note, some numbers are rounded.)] Class D.O.T. Slicks 5 6.56 (* 1.082) 7.10 (* 1.296) 4 8.50 (* 1.082) 9.20 (* 1.296) 3 11.00 (* 1.082) 11.92 (* 1.296) 2 14.30 (* 1.082) 15.45 (* 1.296) 1 18.50 (* 1.082) 20.00 I do not know what multipliers anyone would find desirable, but there is the pattern. Will Quote Link to comment Share on other sites More sharing options...
pocracr Posted October 8, 2009 Share Posted October 8, 2009 Very Very Good.....!!!!!! Sergio Looking at the current cut-offs, and modifying the outliers --> a more rational classing chart would be: [For clarity, this chart lists only the upper limit of each class. (The low limit of each class can be deduced.) (Note, some numbers are rounded.)] Class D.O.T. Slicks 5 6.56 (* 1.082) 7.10 (* 1.296) 4 8.50 (* 1.082) 9.20 (* 1.296) 3 11.00 (* 1.082) 11.92 (* 1.296) 2 14.30 (* 1.082) 15.45 (* 1.296) 1 18.50 (* 1.082) 20.00 I do not know what multipliers anyone would find desirable, but there is the pattern. Will Quote Link to comment Share on other sites More sharing options...
ianacole Posted October 20, 2009 Share Posted October 20, 2009 I don't know if this contributes to the discussion at all, but I calculated the weight differences needed at each class to run DOT vs. Slicks assuming a 200HP (or average) car: Quote Link to comment Share on other sites More sharing options...
RSCoupe Posted October 20, 2009 Share Posted October 20, 2009 I don't know if this contributes to the discussion at all, but I calculated the weight differences needed at each class to run DOT vs. Slicks assuming a 200HP (or average) car: Um, you have the class numbers backwards. Quote Link to comment Share on other sites More sharing options...
ianacole Posted October 20, 2009 Share Posted October 20, 2009 Yah, last thing I did at work...how's this: Quote Link to comment Share on other sites More sharing options...
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