Here's a list of things that really drive me up the wall with SR4.

#1: Diving and decompression.

If you've ever seen divers apparently being paid vast sums of money to just sit around and read the newspaper, there's a pretty good reason for it. Decompression sickness - or "the bends" - is caused by a simple law of physics: the amount of gas you can dissolve in a liquid is a function of how much pressure it's under. When divers go deep under the sea, the pressure is high enough that huge amounts of nitrogen are dumped into the bloodstream, which will go out of solution and bubble out exactly like fizz in a can of cola if you decompress too quickly. If you ascend slowly and gradually depressurize, you can minimize the risk, but you still need to wait around quite a while for the nitrogen to boil away from your bloodstream.

The listed effects of decompression sickness are "one box of physical damage per hour until placed in a pressure tank." It's much worse than that - ascending from 200 meters in 30 minutes will make you exceedingly dead. Also, if you get on an airplane the day after your dive, you get the bends anyway - there's still a lot of nitrogen slowly boiling away from your bloodstream, and it boils away much, much faster under the reduced pressure.

#2: Car modification

This one really puts a bee in my bonnet, if you excuse the incredibly horrible pun. I've seen modifications that violate about half the rules set in Arsenal done by men in sheds. A good example might be the swap between a 1961 3.5 liter Oldsmobile V8 and a 27 liter 1,600HP Rolls-Royce Merlin engine in an old Rover.

I'm not a mechanic, but some of this stuff doesn't even make sense under high-school-level physics:

1. Engine acceleration and top speed upgrades are ridiculous. There's only one thing which an engine produces, and that's brake horsepower. Top speed is a function of mechanical and aerodynamic drag (which varies with speed) and horsepower: when the energy consumed by drag at a given speed is equal to the peak engine output, you've reached your top speed. While it's possible to trade peak output for a little acceleration by tuning your engine for less torque at high RPMs and more at low RPMs, electronic valve systems being developed today would negate the need for a trade-off and a continually various transmission - which allows an engine to sit at peak RPMs while accelerating - means that it would be pointless.

2. Turbochargers, once spun up by exhaust gas, increase engine output by forcing more fuel and air into the engine, allowing for ten liters of fuel and air in a dinky two-liter engine. While efficiency is lost, this does make it to add a lot more power to a small engine in a small car - for example, a heavily boosted motorcycle engine can produce 500 horsepower despite being the size of a breadbox. They engage whenever the engine is working hard (and producing lots of the exhaust gases that power them), and can be seen working throughout fifty-mile courses on pretty much every rally car for the last twenty years.

What Arsenal lists is an overboost. A turbocharger's design means it's as simple as turning a knob to adjust the pressure at which air is forced into the engine, resulting in a bigger bang. However, doing this will overwork the turbo and put more strain on the engine, potentially causing damage.

There are additional flaws to turbochargers. Unless multiple small turbos or (ideally) a complicated sequential turbo system with multiple turbochargers of increasing size is used, a turbocharger can take time to spin up and begin delivering boost. One solution to this problem is an "anti-lag" system, which wastes large amounts of fuel for the sole purpose of keeping the turbo spun up and ready to supply boost. Another solution is to use a supercharger, a less efficient system powered by the driveshaft that has no spin-up lag at all.

3. Engine swaps.

With a little custom fabbing and some spare parts, it's possible to do some pretty weird modifications to cars - for example, I'm told it's quite popular to take the lightened small-block Chevy V8 from a crashed Corvette and put it under the hood of a mid-90's RX7, a car originally famous for it's piston-free Wankel rotary engine. I've seen V12-powered pickup trucks, and a Geo Metro race car powered by a souped up motorcycle engine, and Porsches with Subaru powerplants.

While keeping the aesthetics the same can be hard and not spoiling the handling can be harder, this is a good way for a mechanic with more skill than money to turn a beater into a speed demon.

4. Weight reductions

I may have missed this, but weight reduction is the #1 upgrade to any car ever. Reducing weight improves acceleration, sharpens handling, decreases body roll, and improves fuel economy. Quite a lot of weight in a modern car is from components not related to the mechanical or structural integrity of the vehicle; by ditching the heater, air conditioner, rear seats, thermal insulation, acoustic insulation, nav system, stereo, cupholders, interior body panels, and other unimportant items it's possible to do some pretty impressive things to a generic econobox.

5. Aerodynamic mods
By combining a variety of relatively subtle components - front and rear splitters, a small spoilers, some streamlined fenders - it's possible to make a big difference in performance. By trading downforce for drag, it's possible to vastly improve handling at the expense of top speed There's a reason why Formula One cars need 1,000 horsepower despite weighing about as much as my shoes - all the wings and spoilers that give it the tremendous downforce required to take a corner at 150MPH also result in huge air resistance.

I'm just gonna say these rules are LESS nonsense than some of the shit you could achieve in Rigger 3.

And, in support of your position on engine swaps, allow me to share the following link.
Chevy Matiz with a Corvette Z06 Engine

Facts....

Elves, Dragons, dwarves, trolls, orks, Dragons, Dragons, magic, Technomancers, computers plugged into brains directly, people chopping off limbs and ripping out eyeballs to stuff in machines to replace them... and MAGIC!

Hmm, car mods and the actual effects of the bends would be really low on my list.

Its still real to me!

As I said, it's easier to swallow a big lie than a small one. It's easy to accept a set of arbitrary rules for magic or cybernetics; one is fiction and the other is so far in the future that it may as well be. On the other hand, any day of the week I can walk down the street and see a guy doing something complicated to an old Volkswagen: there are set rules for automobiles, and things get confusing when they're not followed.

Agreed. Math was not the author's strong suit.

Commercial and Navy divers do things that would get someone without their support network very dead. A bunch of their dive profiles include things like rise directly to the surface from some silly depth (skipping the last many hours of Deco) and throw their gear off and get in the waiting chamber within several minutes, with an immediate "chamber dive" to many meters for multiple hours.

Okay, then let your players do whatever they want for car modifications. Seriously, do you expect Shadowrun to have a game mechanic for the effects of swapping in a new cam for your V8? Raising the compression? Putting in a stroker kit? Or how much nitrous you want to dump in at once?

Shadowrun isn't an automotive tuning simulator, its an RPG. The rules are abstracted enough to make things easy and fun. If you want to come up with some more involved auto modification rules, go on ahead.

And the rules for ascending from a dive are to not make something like that too deadly to the players. If the game were completely realistic, it wouldn't be any fun.

I wish the author would've/was allowed to use exponents and possibly other bits of advanced math.

...

...

Traveller ship design rules FTW.

Fun Trumps Realistic almost everytime...

No one wants to have to use a scientific calculator to play a tabletop game.

Stop calling me no one. I may be a nobody but they are different.

For a realistic space tactical game, I'll gladly use a scientific calculator.

But I also love Attack Vector Tactical.

Ken is almost impossible to work with, but he's both brilliant and skilled.

That's the impression I got from the product. Anyone who puts that much detail into something is probably gonna be equally perfectionist with everything else.

Let me just start off by saying, that Shadowrun has enough complex and convoluted rules. It has a LOT of them. A lot a lot. So, they try to simplify things as much as possible. Vehicle riggers want to supe up their westwinds, so they set down some basic rules for the system which aren't terribly realistic but are quick, easy, and let players have the fastest machine on the road if they want to use their money that way. This argument is kinda like "But real life caseless ammo doesn't work" or "Real Life hold out pistols jam very easily." Is it realistic? No. Is it quick, easy, keeps the game moving, and does it allow players to do a bit of tinkering instead of buying stock models? Yes. However, if you want to rationalize:


Not true. I am also not a mechanic, but I have tinkered around with my dirtbikes enough to pick up some stuff. Bikes (and, by extention, cars) can be tuned a lot. A 1969 Dodge Charger has a craptonload of horsepower. It also has great acceleration, but it can't touch some of the sports cars in terms of top speed. Sure, some of it is based on horsepower, but a lot of it is based on how the engine is designed to operate. Some engines, by design, work well in low RPMs. This gives them great acceleration, but when they hit their high end, the run out of juice, and don't go as fast as an engine that hits it's prime in high RPMs. When I was a kid, my Dad tuned his dirtbike for High-end RPMs (by tuning the jets and putting some aftermarket parts on) and tuned mine for Low RPMs (by doing the same.) He would ALWAYS beat me in the straightaways, but I could out-accelerate him from a dead stop.

If you feel that it is that big a detractor from the game, just assume that Engine Tweaking (Accl) increases the horsepower and tunes the engine for low RPMs, Engine Tweaking (Speed) does the same for High RPMs, and doing both is a different process that upgrades the engine's overall effectiveness (and doesn't tweak the powerband of the engine.)


Because there is very little mention of fuel economy in the book, it is entirely possible that turbochargers are the 'anti-lag' variety, and simply waste fuel. But really, the book already mentions something about this. It says that there are a variety of different parts, and they all function differently but produce the same result. Maybe the Turbocharger is really a ramscoop, or it may be that (as the song goes), the system is 'three deuces and a four speed, and a 389.


This one I kinda agree with you on, but I can see why it would mess with Shadowrun Rules. My Uncle had a Malibu SS with a Chevy Smallblock race engine in it. Thing blew away everything on the road (or so I am told, this was before I was born.) But a car is more than the sum of it's engine, and deriving new stats would be difficult. For example, what happens when you put a 'vette's engine in a RX-7? I can tell you one thing, the car does not BECOME a 'vette. It still has a different top speed and rate of acceleration due to drive terrain and aerodynamics. How would you come up with rules for that?

Yeah, okay, you got me on this one. It is true that by making your interior "Spartan" and by replacing things (like your seat) with a lightweight equivelent (like a racing seat) that you can reduce the weight of the car, thus you reduce how much the engine has to work to 'move' you, thus you increase your performance. I would houserule that doing weight reduction increases accl by 5/10 and it increases the top speed by 5%.



Again, this looks like another thing that can be houseruled to me. Charge the same amount of cash as 'pimped out ride' lvl 2 and reduce accl by 5/10 (and top speed by 5%) to increase on-road handling by 1 (hey, handling increase of 1 is VERY big in Shadowrun.) But make it also only usable on road. Aerodynamics like you are talking about require the car to be pretty low to the ground (or, at least, requires the bodymods to be low to the ground), so (like the improved handling upgrade) the car immediately makes a crash test if not on the road.

#3 Weapons in Space. Oh my - they simply copied the horrible mistakes from Target: Wastlands.

Firearms needing pressured Air? To properly cycle a gas-operated gun, perhaps. I'll go bang just fine, like underwater.

Explosives/Grenades/Rockets needing 'inbuilt oxidizers'? Wow, that's really rocket science - Shadowrun obviously has high-powered explosives that work without oxidizers at all in atmosphere and underwater. Who got the Nobel Prize for that one? All modern explosives (that includes gun powder) need internal oxidizers to work at all.

You mean...this isn't real? Well then some one tell the damn dragon living in my closet!

I mean really, you ever try to clean up after one of those...ick,

For one thing, yes a normal gun will fire underwater . . . ONCE. However, once the insides get wet, that little hammer thing (the thing that ignites the explosive in the bullet, y'know?) won't work so well. And . . . same with space. If there is no O2 for the hammer to case spark, then I would imagine the gun wouldn't work.

And, uh, the thing about grenades . . . you see. . . . Yes grenades work perfectly fine underwater. HOWEVER, exploding a grenade underwater changes the physics of what happens after the explosion. Shrapnel is slowed down pretty quickly by water resistance. The heat from the blast is disipated pretty quickly. The pressure wave has a lot less power, because it has to move stuff that is a LOT more dense (water vs. Air.) In the end, detonating an explosive underwater changes up all sorts of rules.

Oh, and tossing a grenade in space? Yeah, it'll explode, and there will be nothing to impede the shrapnel . . . but there is no presure wave. There is no air. So an HE explosive would be pretty uselsess. Lots of heat for those standing right next to it, but those a bit outside of that? Nothing.

It does, see Mythbusters.

If you are using a blackpowder-flintlock gun. Otherwise, the hammer of, say, a revolver will strike the internal ignition cap just fine. And since the revolver doesn't rely on the balance of atmospheric pressure to internal pressure to cycle, it will do so.

Indeed. And the rules even account for that... unlike the rules fpr space, that make us some really strange stuff.

Actually, a pressure wave under water is a lot more terrible than in air - even the rules account for that. That why there is dynamite fishing and deep charges.

Of course there is - it just will fade away quickly, since the only thing carrying it are the rapidly expanding gases that actually form the explosion - because that's what the explosive turns into. Holding onto an armed HE grenade or some C12 is still a very bad idea in space.

Lesson learned:
Underwater, use HE, in space, use AP/AV. And don't by the snakeoil called 'extra internal oxidizers for space' - your fixer is secretly laughing himself sick at the thought of charging you idiocy.

Although i would have to wonder at the sanity of a runner using such weapons in space in the first place...

Yeah, that's what Gauss and Laser are there for ^^
And i imagine most Combat will not take place in a vakuum, but in an air filled low gravity environment.
And in there, Guns and explosives work just fine, like they would on the ground. If there was enough space in the station(i kill myself with those puns), a bullet would actually fly for a longer time, because there's no drop due to gravity. Only Air-Friction to slow it down gradually, and that will love you long time.
Also, inside Spess-Stettions(Spess Mehrens), i would advise in solely using gel rounds, sonic weapons, stick and shock and flechette ammo . . everything else just screams suicide killer.

And i still want my "Shadowrun: IIN SPAACEE!"-Book <.< . .

Dragon's feces could have interesting alchemical applications; just because it's dreck doesn't mean it isn't valuable, alot of stuf people buy is dreck but people are willing to pay hard cash for it.

So you tried to play Aftermath, too, eh? That game...oy!

Like installing a full size rotary engine off an airplane into a motorcycle?



-karma

How about a fully functional backhoe into a 1954 Cadillac Herse?

You're all alone, dude.

There's no way I'd be doing this without a spreadsheet, or at least a TI89. A scientific calculator simply won't cut the mustard.



This one is pretty easy. Engine upgrades (any type) increase both acceleration and top speed, and some cars (as listed in the rules) are cheaper or more expensive to upgrade the other. Nitrous would be solved by adding a variable bonus to acceleration and top speed and a variable change of engine damage - the faster the go, the more risk you take.



This is a simple question of aerodynamics - a 1969 Dodge Charger is a brick with wheels, while the roughly equally powerful Ferrari Daytona will hit about 175mph. This is because drag increases roughly to the square of velocity. (Air does funny things at high speeds, but it's close enough for approximation.) While a Charger will murder the XJ220 in 0-60 times due to greater low-end torque, the amount of aerodynamic resistance on the Charger is nearly triple that of the daytona. Horsepower is horsepower.



This is true. However, in the future, it's a moot point thanks to a marvellous invention: The continually variable transmission. A performance CVT can reduce its' gear ratio so low that redline is hit within a second, at which point the gear ratio is increased with speed, leaving the car sitting just below redline and producing peak power as long as you push down the loud pedal. You can find CVTs just like this in many Nissan and Ford products, though at the moment they still need a lot of work.

You're also working with dead technology. EFI and electronic ignition already allow some control of tuning on-the-fly, and systems that would replace camshafts with solenoids to open and close valves allow valve timing to be changed in respect to engine RPM. FIAT and Ford already have working prototypes. And electric cars produce gobs of torque at all RPMs.



The turbocharger is a "Fast and Furious" push-the-red-button affair. It is not something you find on a tractor to aid in pulling stumps. Which is what turbochargers do.

I'd call a turbo a power boost, but as a cost multiplier based on the engine it's applied to along with upgrades (to reflect the fact that a turbocharging system is proportional to the current fuel/air use (and power) of the engine) that would reduce reliability under use, would kill fuel economy, and would not engage for one combat turn unless the driver had activated the gas-guzzling anti-lag system ahead of time.

If I may add a little to Rotbart's post, an explosive blast wave's total energy is reduced by crushing things. Air is crushable, so an explosion in air wastes power making those cool visible blast waves and fireballs that could otherwise be smacking something.

Water is not crushable. An underwater blast wave will go on and on until it finds something to crush, like fish, coral, or YOU.

Of course, as the explosion gets larger, the total energy is spread over more and more area, so a man sized patch of the wavefront will contain less and less energy as you get farther and farther from the point of detonation.

I was of the understanding that water was less crushable, not simply uncrushable. Otherwise, there would be no longitudinal wave attenuation, and the water hammer effect would make civil and mechanical engineers very sad.

Although, to be fair, I did electrical and computer engineering, so I might be way off on this.

yeah that pretty much says it for me.

Shadowrunner cars are supposed to be ludicrously fast. The whole point of being a rigger is that you can keep a car on the roads at speeds that normal people simply cannot handle.

Besides, there's two ways to make a car fast: You build it sanely, which is expensive, or insanely, which isn't. Runners generally don't care if a car is full of sharp edges, noisy, cramped, and in need of a full work-over after each use if it saves their bacon just once.

This also opens many opportunities for stealth and subterfuge. A really clever runner with access to a pretty good machine shop and a TIG welder can build a top-spec spaceframe capable of accelerating fast enough to cause whiplash....covered with the body panels of a Mercury Comet. If you tint the windows (to keep people from seeing the complete absence of an interior and the heavy-duty rollcage) and find a way to keep the engine noise the same, you have the ultimate stealth vehicle - an econobox indistinguishable from millions of other econoboxes....until you push the accelerator past ten percent.

All I can say is James May's Aston Martin is to Shadowrun's Arsenal Rules on Vehicles. Further details on Top Gear's Challenge to Find Driving Heaven

Yes, very true. However, it is also true that WATER weighs a heckofalot more than air. So the energy required to create a damaging pressure wave in water is higher than the energy required to create a pressure wave in air. So, again, blowing up a grenade underwater point blank is a very bad idea, as the wave is more damaging. But it will dissipate much faster in water, as it has MUCH more weight to move with the same amount of energy.

However, there is a (navy?) recruit who was doing basic training and accidentally set off a grenade and dropped it. Not knowing where it was the best thing to do was to jump off the dock and into the water (avoid the blast).

Unfortunately for him the grenade had also rolled into the water.

Instead of merely being caught in a shrapnel storm and maybe surviving he was subject to the shockwave underwater.

He died.

I don't believe it works that way. Pressure is what we truly care about. Pressure and compressability, which acts against pressure by absorbing an amount of energy from the explosion.

We can look at the transfer of energy from an explosive to a target by considering only the cone of the media between the explosive and the target, which acts like a slightly sprung rod. You put a force in at one end and it is exerted at the other, minus the amount of force lost compressing the spring. Since the blastwave in the adjacent regions of water propagates at roughly the same speed we don't have a pressing need to account for pressure bleeding into the surrounding area, simplifying our model considerably.

Due to its higher density water is far less compressable than air which leads to more of the original force being transferred into the target. Water is more dangerous a medium to be near a detonating explosive in. Compressibility is expressed per unit volume, meaning that the amount of energy lost to compression increases with distance as well as the pressure dropping off according to the inverse square relationship area has with distance.

Thus, the blast wave travels further before it falls into the safe pressure boundary because less energy is lost in compressing the medium per unit distance from the explosion source to the target.

In simple terms for Degausser:

The more the water is moved (aka compressed), the less powerful the explosion is. So, precisely because it is more difficult to move water than air, the shockwave is more powerful & spreads over a larger area.

It's not about 'swallowing the big lie'. We just don't have anything to compare the rest of the stuff to. I mean, if there were real dragons in the world, everyone would be making links to how they've gotten the armor rules for dragons wrong because of a youtube video that shows the thickness of dragon armor. Or we'd have arguments about how magician 'X' can do this feat of magic that is supposed to be 'impossible' by the rules.

Without real world examples, you can't make claims that the rules are factually inaccurate.

James May's Aston Martin N24 has, if I'm not mistaken, about half the upgrades I just listed. It's not a car that any normal person would buy, but a shadowrunner would doubtless take all the spartan horribleness of a race car in return for the ability to outrun almost any car in existence.

James' car also brings up a rather interesting part of the whole acceleration-vs.-top-speed debate - acceleration drops off quite quickly after a given speed for any given vehicle, and at low speeds is limited by the grip of the wheels upon the ground. A 300HP Mitsubishi Lancer Evo can hit 60 faster than a 420HP BMW M3 because the BMW, were the accelerator to be pushed down hard, would just spin the wheels - half the potential grip of the tires is wasted on the front wheels, wheras the Mitsubishi can use all of it. On the other hand, above 60MPH the Subaru must trade RPMs for torque, slowing its' acceleration, while the BMW has power to burn and aerodynamic downforce that gives even more rear grip. Formula One cars actually accelerate faster above 60mph - their tiny mass gives almost no grip at low speeds, but huge spoilers can increase the effective weight of the car fivefold.

(It helps to think of it a lot like relativistic physics: accelerating from standing to 1*10^8 mph is a lot easier than accelerating from 1*10^8 to 2*10^8.)

Of course, implementing this properly would be impossible outside of a video game. That said, I'm going to be running a SR4 game soon and am very much tempted to rejigger the rules a bit - perhaps a second "top speed" after which acceleration is halved?



That's my point. It's all well and reasonable to play a game with arbitrary rules for dragons because dragons are, themselves, arbitrary creations - they are whatever we say they are, since they don't actually exist. You can tell me that a dragon's secret weakness is chocolate, and I'll accept it.

On the other hand, an engine block is not an arbitrary object. Regardless of what a book tells me, I know that it's a huge lump of some sort of metal with lots and lots of holes in it, almost always in one of a few popular shapes. I am not going to accept that an engine block is small, yellow, and squeaks.

It is, truely.

Sometimes its cheesecake though. Wyrm would eat anything between him and a cheesecake in order to make sure he ate the cheesecake.

Exactly. You just have to get the feel right. One of the ways you maintain verisimilitude is by getting the things that people KNOW right.

Or a jet-engine VW bug?