This is all the numerical data I could find over two days of matchups. To my knowledge, it is accurate, but please let me know if you find anything that needs amending.
Character HP: Roadkill: 120 Twister: 95 Axel: 130 Mr. Slam: 140 Shadow: 120 Sweet Tooth: 140 Minion: 230 Hammerhead: 130 Outlaw: 120 Warthog: 150 Mr. Grimm: 85 Grasshopper: 110 Thumper: 120 Spectre: 110
Top speed/Turbo speed Roadkill: 117/156 Twister: 140/178 Axel: 101/138 Mr. Slam: 91/138 Shadow: 112/149 Sweet Tooth: 91/138 Minion: 126/168 Hammerhead: 94/138 Outlaw: 126/168 Warthog: 100/138 Mr. Grimm: 124/166 Grasshopper: 119/157 Thumper: 110/147 Spectre: 129/171 (Note: some of the faster characters like Grasshopper and Spectre can use a glitch to add 2 mph to their max turbo speed when turning off a ramp)
Special weapon generation time in seconds/maximum number of specials in inventory Roadkill: 35/5 Twister: 18/3 Axel: 35/5 Mr. Slam: 50/3 Shadow: 20/5 Sweet Tooth: 18/5 Minion: 18/5 Hammerhead: 60/5 Outlaw: 55/3 Warthog: 35/5 Mr. Grimm: 70/3 Grasshopper: 35/5 Thumper: 80/5 Spectre: 35/4
Pickup weapons: Fire missile: 7 dmg Homing missile: 10 dmg Power missile: 15 dmg Remote bomb: 25 dmg on direct hit, decreases with distance from bomb Napalm: 10 base dmg plus fire damage Ricochet: 7 base dmg, increases to up to 15 dmg with rebounds (note: the first rebound adds pushback, but does not add damage. Damage increases after several rebounds) Lightning: 20 dmg (2 hits, 10 dmg each)
Universal damagers: Freeze missile: 7 dmg Mine: 15 dmg Machine gun: ~2.9-3.6 dmg per second (bullets do not guarantee damage. Pressing the R2 button does not fire a bullet, but instead plays the firing animation for however long the button is held. The rate of damage is partly randomized. Bullets that do hit deal 1 dmg each) Fire damage: ~4-6 dmg per second (flames stay for 5 seconds if not extinguished with water or turbo. Rate of damage is partly randomized) Lava damage: ~2.7 dmg per second
Specials: Roadkill: 10 dmg on initial fire, increases to 40 dmg on return trip Twister: Minimum dmg is 4 on drive-by hit, maximum is 30 when opponent's grill faces tornado upon activation. Total damage depends on the angle of impact and how long opponent is held in tornado, and can be potentially increased with collisions. Axel: 15 dmg Mr. Slam: 10 dmg per slam, special includes up to 4 total slams for maximum of 40 dmg total. Against Hammerhead and Minion, special never allows more than 1 slam, but damage is always 25. Shadow: Base damage ranges from 9-24. 24 dmg on direct hit, damage decreases to minimum of 9 with distance from detonation. If the special is detonated on a sloped angle (e.g. Amazonia bridges), 24 dmg is added to the base dmg for a maximum of 48 dmg. Sweet Tooth: 15 dmg Minion: 10 dmg per missile plus 7 dmg from freeze for total maximum of 37 dmg. Missiles decrease to 2 dmg each if fired from long distance. Hammerhead: 15 dmg added onto base ram damage Outlaw: 2 hits, 10 dmg each for 20 dmg total. Warthog: 6 dmg per missile for total of 18 dmg, missiles decrease to 2 dmg each if fired from long distance. Mr. Grimm: 40 dmg Grasshopper: 15 dmg Thumper: 1-60 dmg over time plus fire damage Spectre: 12 dmg
Ram damage: Many variables affect ramming damage to the point that it's impossible to give an accurate summary of how it works without accessing the source code and creating various matchup charts. Below are notable variables.
Armor of the attacker in relation to the victim: Characters with higher armor deal more ramming damage to those with lower base HP. Mr. Grimm takes the most damage from rams and deals the least damage while Minion takes the least damage and deals the most, save for Axel.
Speed of attacker at impact: Nudging the opponent at minimum speed deals zero or low damage while faster rams or turbo ramming increases damage. Most low speed rams deal 3 damage or less.
The angle of impact: Characters take more damage at different angles. For example, certain characters are most vulnerable on the driver side door. Damage increases accordingly.
Ramming is most important for higher armor characters. These are some damage ranges I've found when comparing ramming Mr. Grimm and Minion. Axel: 15 base damage against all characters (low speed nudging included), maximum ram damage increases to 20-45 dmg based on opponent. Hammerhead: Max damage 20-40 based on opponent. Mr. Slam, Warthog, Sweet Tooth: Max damage 25-32 based on opponent. Minion: Max damage 35-40 based on opponent.
