N/A 10.5 RULES.. these rules are somewhat to help keep the field level..
that is only part of the rules, the rest of the rules dictate the required weights for big block as well as small block combinations.
To keep the field level Big Blocks have to weigh more than small blocks at the same cubic inch.
SMALL BLOCK BASE WEIGHT (max cubic inch 470)
300 = 2400 + Over 300 add 1.25 lbs. per cubic inch
340 = 2450 + Over 340 add 2.50 lbs. per cubic inch
360 = 2500 + Over 360 add 2.75 lbs. per cubic inch
380 = 2555 + Over 380 add 2.70 lbs. per cubic inch
400 = 2609 + Over 400 add 2.65 lbs. per cubic inch
420 = 2662 + Over 420 add 2.60 lbs. per cubic inch
440 = 2714 + Over 440 add 2.55 lbs. per cubic inch
460 = 2765 + Over 460 add 2.50 lbs. per cubic inch
470 = 2815
BIG BLOCK BASE WEIGHT (max cubic inch 640)
440 = 2860 + Over 440 add 2.60 lbs per cubic inch
460 = 2900 + Over 460 add 2.55 lbs per cubic inch
480 = 2940 + Over 480 add 2.50 lbs per cubic inch
500 = 2990 + Over 500 add 2.45 lbs. per cubic inch
520 = 3039 + Over 520 add 2.40 lbs. per cubic inch
540 = 3086 + Over 540 add 2.35 lbs. per cubic inch
560 = 3133 + Over 560 add 2.25 lbs. per cubic inch
580 = 3178 + Over 580 add 2.10 lbs. per cubic inch
600 = 3220 + Over 600 add 2.00 lbs. per cubic inch
620 = 3260 + Over 620 add 1.80 lbs. per cubic inch
640 = 3296
Even with the deduction of 125 lbs the big block still has to weigh slightly more than the small.
Not sure if I agree but the example of the N/A class would suggest that Big Block are quicker per cubic inch.
