Was messing around with a solo game of 2.5e Car Wars. Its a tabletop game of car combat that's frankly so complex only an autistic person like me could like it. The local used book store had a treasure trove of old ADQ magazines for it which led to me fucking with it today in table sim.
Anyways, I know its like 30 years old but the old black-n-green compendium rules are kinda shoddily written. The target mods really should've had their signs swapped; you start with a target number based on the gun in question, and modify that target from there, but the modifiers are written as if your modding the die roll instead of the number you're looking for. It's also hard as hell to hit anything but that's another story.
The real wild goose chase was part of the rules for collisions. I knew that vehicles with metal armor took collision damage differently, but couldn't for the life of me find where in the book it tells you that.
1) The actual section on collisions don't mention it. Collisions in Car Wars are a "grappling in RPGs" level of rules snafus, its several charts and rules procedures nearly guaranteed to grind a game to a halt. Basically, the relative speed and weight of each party is a factor, in addition to who hit who where, such that head-on, t-bone, and sideswipe collisions have their own list of procedures. The section's actually quite short, but dense. What actually matters is, metal armor isn't mentioned at all here. In fact in a post "after this problem" reading, the rules for collision damage isn't actually here at all. You'll get your damage value but not actually how to apply it to your vehicle, at least beyond ticking off (plastic) armor on the side and an optional crew stunning mechanic. Incidentally, neither relevant equipment to ramming, ram plates or bumper spikes, get a mention here either.
2) The section on metal armor in the car construction rules doesn't mention it either. It mentions all the other benefits of metal armor, how it works for shooting attacks (which is an entire different mechanic), plus the obvious construction parts such as weight and cost. Nothing about collision damage. I checked the ram plate section as well but it's just the rules for the ram plate, which admittedly doesn't need metal armor to work. (it helps, tho)
3) The book's index doesn't work, checking both "collision" and "metal armor" listings sends you to a random page of boat movement. I'll probably never make use of the boat rules...
4) I checked the "catalogue from hell" book, a compilation of all the construction rules and options, the metal armor section is identical to the main compendium. So no mention of collision damage for metal armor there either.
5) My last hail mary was to dig out the reprint I have of the Classic Car Wars box. It's rule book has a working index.
Collision damage is a part of the damage section of the combat chapter, basically the tail end of the rules for shooting people. In addition to the rest of how collision damage is applied (if it bypasses armor, all exposed components get damaged equally instead of hitting one) here and only here is the rule for metal armor. It absorbs 3 times the impact damage and you can only lose up to half of it from a single impact.
Granted the truck in question rolled into the arena wall at 70 mph and took like 40+ damage totaling it instantly and actually running the numbers was a total waste of time but the rules search still annoyed the piss of me.
Though it is funny how this game takes place some 20 years from now but car tech never advanced beyond like 1970. Radial tires are an upgrade, so are antilock brakes. Rules-wise they handle like 70's shitboxes, taking corners at any real speed is a dangerous proposition without significant performance upgrades. Acceleration is also quite shite, 0-60 is often 6-12 seconds. Oddly gas engines default to fuel injection, carburetors are a separate downgrade that decreases engine cost (and power). Actual body streamlining is also an upgrade, so I guess default car bodies are brick shaped.