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Arena Vehicle Design in Car Wars 1996 Edition

There have been three major articles published about arena car design -- the two most influential written by Tim Ray. These two articles contain most of the important aspects, however there are a number of details which I feel are worth further discussion.

David Gregg
IADA President
July 1996


There is a tendency to choose a body type first, and then see what can be fitted into it. A better approach might be to choose the basic weapon systems, accessories, tires, etc., and then decide what body to put it in.

Generally, I try to use the largest chassis that I can afford. A larger chassis allows more spaces of weapons to be mounted per side and divides the weight of heavy components over a greater weight per point of armour.  A larger chassis can also hold more spaces of component armour.

Smaller chassis can carry more armour and so are suitable for rabbits, and ram cars. They are cheaper and require a smaller engine. A sloped compact can be particularly effective.


With modern, more accurate weapons, tires are more vulnerable than ever. Tim Ray's standard is the steelbelted solid. With only 16 DP, they almost certainly need wheelguards which will bring the cost per wheel up to $850 amd 152.5 lbs. A better buy in higher divisions might be plasticores for only $150 extra each which will have 25 DP and are fireproof to boot. (If you still want to discourage tire shots, fireproof fake wheelguards can be useful. For those with nerves of steel SB PRs with wheelguards are cheap, but watch out for explosive tipped spikes.


It is difficult to disagree with Tim Ray's discussion of weapons.

One weapon which he neglects to mention, however, is the heavy MG. the HMG only takes one space, yet holds 20 shots and with HD ammo does 2D+1 damage. It is perfect for two turret mounting, three or four on one side, or just to save space.

Another particularly nasty weapon is linked, bumper triggered oil and ice dischargers on the side of your car. Bumper triggers fire before the collision so the oil and ice will fire before the effects of the collision occur. Any car colliding with you from the side will get a nasty plus on the hazard they take from the collision and there is a good chance that it will lose control if it is going too fast. Excellent for killing those foolish enough to try to T-bone you.

There was a time when entering an arena without a ramplate was nothing short of insanity. Since the rules have been changed, it is possible to survive without one. Purely from a weight point of view, a ramplate reduces the front armour by 33%. It reduces damage from collisions by 29% (3.5 per die minus 1) and collisions with ramplates by 18% (5.5 per die minus 1). So from the point of view of surviving the collision, a car is better without a ramplate. However, a ramplate will inflict serious damage on an opponent, so it can be a very powerful offensive weapon, even if its defensive value is reduced.

Finally, one largely unnoticed rules change in the Car Wars Compendium is that spikes now do half damage to solids and plasticores, rather than no damage.


Metal armour is past its prime. High damage new weapons easily pierce all but the heaviest metal armour. To add insult to injury, HESH ammunition can destroy large amounts of metal armour and can cause internals without penetrating the metal. In order for metal to be worth the weight it has to be thick enough to stop the average damage from the weapon they meet most often in the division. This is now much more difficult since duelists often take one large weapon rather than two small linked ones.

The advantages of metal remain that it is cheap, fireproof and resistant to collisions. Five points as an outer layer on a ramplate work just great. Generally, if you can afford, it, plastic is a better buy.

Fireproof plastic is far too expensive. If you are worried about fire, a fire extinguisher is often a better buy. Laser reflective metal can be worthwhile if you have some spare money. Laser reflective plastic is heavy and expensive. If an opponent has wasted his/her money on a laser, you probably have enough of an edge already.

In my opinion, the real star of defense is component armour. Many players regard component armour as a cheap, light supplement to external armour. There is a tendency to component armour the smallest components to save weight and space. To do this is to massively underestimate the importance of component armour.

Component armour is a floating armour that protects internal components no matter what side the damage comes from. If all the internal components in a vehicle are component armoured, there may be no need to use top or underbody armour. The component armour will absorb damage from wherever it comes.

Component armour is also a protection against fire. If all the important components are armoured, the vehicle has a certain amount of breathing space to put out a fire. In addition, according to ADQ X/X, a volatile weapon cannot cause a vehicle to explode as long as it is protected by component armour. This is very useful for fire bugs afraid of exploding.

Component armour also protects vehicles from T-bone rams. T-bone damage is divided equally between crew, cargo and engine. Thus, the damage is divided equally between the component armour on each, so a ram car must do serious amounts of T-bone damage to kill a car. A few points of rubber component armour can help the truly ram paranoid.

Sloping your armour is nothing more than a big sign on your car telling your opponents to shoot at your tires. Its fine if you have expensive tires or the ranges in the arena are large, but otherwise it seems like a big consumer of space.


Usually, most duelists take a single driver without much thought. It is unusual to see a gunner. However the crew rules in ADQ 9/1 make a second crew member more valuable. A crewmember may be driver +2 gunner +1 or vice versa. With reflex rolls set at 4, this essentially amounts to a choice between +2 HC and +1 to hit and +1 HC and +2 to hit.

A gunner allows both +2 to hit and +2 HC, gives an extra firing action, and provides an extra target to be hit in the crew compartment. Gunners are free (much cheaper than a HRSWC or radial tires) and fairly light. Their only disadvantage is that they take two spaces.

Tragically, passengers are no longer allowed in AADA duels.


Unless money is a serious problem, gas power plants are the only way to go. Generally, the best gas engine is the smallest one. Gas engines are expensive, so a carburetor or MB carb can be a budget saver. If acceleration is important, then use a turbocharger. If top speed is vital use overdrive. If budget allows, a variable pitch turbocharger will get you the lightest engine.


Tim Ray neglects trikes as a viable design strategy for the arena. However, they have a number of features that deserve more attention. The big advantage of trikes is in the weight and space of their power plants. An electric trike power plant will weigh about 600 lbs less than the one needed to power a similarly sized car. This nicely offsets the lower weight capacity of trikes. This only applies where cars *must* use electric power plants. If cars are allowed to use gas power plants (as in the case in most arenas), trikes no longer have the plant weight and space advantage.

When using a trike, just about the only type worth considering in the mid (15-15) divisions is a reversed trike. The advantages of reversed trikes are manifold, but include a +1 HC and the ability to use spoilers and airdams. A trike may also use weapons from both side arcs into the front (rear) arc together. Unfortunately, it appears that you need a smart link ($500) to fire weapons on different sides together and you need a non-single-weapon computer to gain a targeting bonus.

The big disadvantage of trikes is that they only have three wheels. If a car loses a wheel it is a serious blow. A trike that loses a wheel is immobilised. For this reason, in my opinion, you should always get the best tires you can possibly afford. Trike tires weigh half the amount of car ones, and you only need three of them, so weight isn't a problem. If you can possibly afford the $3000 for plasticores, they are well worth the investment.

Because of their light weight and relatively large number of spaces, trikes make excellent racing vehicles. Some AADA competitions involve races. For example, a standard event is a race in the Double Drum.


One of the most useful accessories that an electrically powered car can possess costs nothing and weighs nothing, but takes one space. An empty cargo space adds a cargo compartment to a car and reduces the chance of an internal being hit by a shot that breaches the side, top or bottom of a car by one third. It also makes it much easier to survive T-bone rams. The gas tank of a car with a gas engine counts as cargo, so a gas engine car gets a cargo area without having to waste a space. (Gas engines are far too powerful.)


It is very important to have some strategy in mind for winning an arena event. As Tim Ray tells us, it is important to design your car for the particular event you're entering and no other. Your car must be designed with some strategy in mind for accumulating points toward victory.

Study the points system very carefully for any arena event. If points are allocated solely for kills then any of the aggressive strategies can be effective. If the last survivor wins, a vulture strategy might work better, since you want to score the odd kill, but basically want to avoid combat.

If points are awarded for shooting targets on the walls then a tire-shooter will have an advantage. Where jumps must be made or checkpoints crossed, the ram-car with its speed and maneuverability is an excellent choice. (It is rather ironic that while the AADA complained about the excessive power of the ram-car, they hosted events that gave it an advantage).

The important thing when entering a points event is to do the things that score points. Autodueling is great fun with your friends at home, but if the competition gives more points for crossing checkpoints then killing cars, then crossing checkpoints is what you must do.

I am no expert on each of the specific strategies (except perhaps the tortoise, which I have been forced to play again and again versus players with vendettas), but here are some suggestions for some of the issues in designing them. Once again, this article is designed to provoke comment and discussion, more than to be an authoritative work. In each section I mention the person who first introduced me to the strategy.

THE LION -- Tim Ray

A popular weapon with lions in all divisions is the AT gun with APFSDS ammunition. This cheap, high damage weapon inflicts an average of 16.5 points of damage per shot, costs only $3000 and takes 3 spaces. It has done more to retire metal armour than any other weapon. In the lower divisions it is cheap, and it is still seen in the higher divisions (often linked in pairs) because nothing else equals its damage. The main problem with the AT is that it cannot be mounted to the side and so it is difficult to gain advantages from maneuvering.

The blast cannon is another popular weapon for aggressive players seen in the mid to higher divisions. The main advantage of the blast cannon is that it can be mounted on the side of a car.

The main alternatives to a single large gun is a pair of linked smaller ones. Smaller guns are usually better value for weight or space. They also have a more flexible choice of ammunition. Smaller weapons depend on your opponents not using metal armour. Against plastic, linked smaller weapons are usually superior but they are very weak against composite metal/plastic armour. Once must hope that the threat of lions with ATs will keep metal armour of the arena.

THE RAM CAR -- Phil Radley

Until recently, the ramplate was the king of of all weapons. One could easily inflict 80+ points of damage on your opponent and take very little damage in return. Ramming was always a risky strategy since it involves getting very close and dangerous maneuvers and hazards, though. These days, a ramplate does fairly little damage but the ram car strategy is still useful in arenas that need good handling and speed anyway.

The secret of building a dedicated ram car is to avoid using weapons. Your money should be spent on the best tires, heavy armour, acceleration, top speed and every other handling gadget. A dropped weapon is something to consider to discourage tailgaters, but no other money or space should be wasted on weapons (except perhaps a vehicular shotgun for shooting targets on walls).


The rabbit is similar to the ram car in construction, but its main tactics in the arena are to run away from other duelists and to cross checkpoints. The tortoise is a car that is very heavily armoured in order to make it almost impervious to attack and tends to move quite fast to avoid being hit. It is often used by players who are especially targeted by other players because of their reputation for being the best.


A tire shooter needs very accurate weapons, so only those weapons that hit on a six are really contenders. In the lower divisions the FT and HDFT are excellent. As the budget goes up, HT ammo is added to the flamethrowers. In the mid divisions the Vulcan MG is good, but heavy, and in big budget land the laser guided RL is the weapon of choice.

The main difference between shooting tires and shooting armour is that you don't need to worry about metal, so linked weapons are just as good as a single large one. Furthermore, the only fireproof tires you will ever encounter are plasticores, which are quite rare even in the higher divisions.


Given that metal armour is going out of fashion and the enormous space and weight advantages of gas engines, the fire bug is a very viable design strategy. Plastic armour just cries out to be set on fire and gas engines reduce the effects of fire extinguishers and explode easily.

If you are trying to defend against fire bugs, component armour is useful, but there is no substitute for a fire extinguisher. Fireproof is too expensive. Metal armour will get you killed by someone with a big gun.

Published by David Gregg, July 22, 1996.
Reprinted by the Seattle Washington Autoduel Team, March 08, 1998.
Updated March 31, 2015.
Original URL: http://arrakis.ucd.ie/~greggd/IADA.html
Original URL: http://arrakis.ucd.ie/~greggd/cardesign.html