Every dirt rating from 0 to 255 and the surface and going it favours. The number is two halves: the upper half (H) leans dirt, the lower half (L) leans wet going. Switch between the stock game and the Rebalance test build to see why 255 was the only answer, and what changes.
Rows: H, upper half (dirt lean) 0 to 15Columns: L, lower half (wet lean) 0 to 15Cell: the dirt number on the card
Colour = the condition where that number stands out most against the other 255. Stronger colour = clearer specialty. Grey = no clear lean. Hover or tap a cell for its numbers.
Look up a horse
Its surface bonus, condition by condition
Additions to the horse's speed term in the race engine, for the build selected above. "vs 255" is this number minus what a 255 horse gets in the same race. Positive means it beats 255 there.
Condition
Bonus
vs 255
Where it sits (0 to 255)
How to read it
Stock Rev C: H only ever helps (on dirt) and L only ever helps (on all dirt and on soft or heavy turf). On firm turf the number does nothing at all. So in this one surface-and-going term 255 is never worse than any other number, anywhere, and the only "specialty" left is how much you give up by not being 255. That is the whole Thunder Boy story. (The numbers are not a ladder: 32 is worse than 17 on soft going because 32 has a lower L. Raising a half helps; raising the whole number need not.)
Rebalance (RB01, build B2 + S1): H still helps on dirt but now costs the same horse on turf in every going. Low L helps on firm going, high L helps on wet going. The adjustments are centred, so averaged over the game's nominal race program and going table all 256 numbers get the same bonus (actual weather, selection and whole careers are unmeasured); what changes is where each one is strong. 255 keeps wet dirt.
These are one term in the speed calculation. Stats, running style, distance, hearts, traffic and your riding still decide races. How many seconds a specialty is worth is what the Rebalance cabinet test is measuring.
Firm going here means Good and Good to Soft; wet means Soft and Heavy. The map uses Good and Soft; the table shows all four.
Source: the Rev C race engine's surface and going routine, decoded from the game program and checked instruction by instruction (doc-ops research, October 2026). Rebalance coefficients are the B2 build running on the Rev C Rebalance cabinet.