Research for a screenplay - Need tech guidance

I’m writing a scene for a screenplay involving a 1956 porsche on a racetrack. I need something to go wrong with the drivetrain that would render the car un-driveable until repair, as a result of pushing it too hard (if it could involve smoke, that’d be great): What goes wrong? I’m an ignoramus when it comes to tech stuff, so please be gentle. Thanks so much.

A 1956 Porsche on a racetrack would likely be the 550 Spyder, or RS. In 1956 it ran the new style Type 547 engine. This engine was a 4 pot air-cooled engine with 4 camshafts. It’s 110 hp may seem puny today, but in such a light chassis as the 550 Spyder, it became a world beater.

Catastrophic failure of a little high strung air cooled engine of this era would probably come from over heated lubrication breaking down. There was no Mobil-1 synthetic in 1956. Main bearings, crankshaft and connecting rods could all go quite quickly producing a smokey death of the engine.

Seek out a classic Porsche forum and enlist someone to fill in pro-bono in exchange for a Technical Advisor credit. The authenticity will add to your effort and Porsche enthusiasts will love you.

You guys are awesome. Thanks.

The best ideas will depend on the particulars of the story and the scene. Not knowing any of the particulars of the rest of the story, the first thing that comes to mind is a broken drive shaft or a broken universal joint. Those would not involve smoke, but having one break on the race track could be pretty dramatic. I am not familiar with this car, so this might not be the best idea, but I think the best ideas will come from people who don’t just know the car, but people who also know the characters and the story.

Assuming you’re looking for a problem that is not catastrophic and would cause the car to pull out of the race but yet could be repaired and the car sent back on the track you might consider the possibility of a leaking oil cooler or cooler line.

A sudden leak appears there and you could have a cloud of smoke not only from the engine oil itself but if the race track was oiled down by engine oil suddenly being dumped on the track in front of a tire(s) the car would spin out and lead to even more smoke rolling off of the tires themselves.

Fluid loss (engine oil, transmission oil/fluid, coolant when applicable, etc.) is a common reason for smoke clouds, spins, and even devastating crashes during any kind of racing.

1955 Porsche doesn’t have a drive shaft or a universal joint. What you have break in the story has to match how long you want it to take to fix it.It makes a difference if our Porsche is back on the track in 10 minutes or out for the day

Ideally it’d be something that wasn’t repairable on the track. I need to justify getting it off the track and into the shop. Is the drive shaft the same as the crank shaft? (I can hear car experts gasping and whincing…sorry). Ha.

No, the crank shaft is inside the engine and is turned by the force created in the cylinders. The drive shaft connects the transmission to the drive wheels. The 1955 Porsche didn’t have a drive shaft though, and a crank shaft repair would require a lot of labor.

Maybe this will help: The transmission transmits torque from the crank shaft to the drive shaft.

this actually sounds perfect. i need the drivetrain to be replaced, so if the crank shaft is shot would that justify installing a new drivetrain, or elements of the drivetrain? And if the '55 didn’t have a drive shaft, what connected the transmission to the drive wheels? Thanks again.

That’s a good question. I would like to know that too. So, will you please enlighten us, nordby?

Typically, the drivetrain consists of everything that propels the vehicle. It usually includes the engine (but not accessories), the transmission, and the drive shaft. So “drivetrain” is too generic of a term. Just take a look at the items that are covered by “drivetrain” warranties.

How about a plain old burned out clutch? That would certainly disable the car and could even be accompanied by smoke, especially in a racing situation.

If you want info on the Porsche 550 Spyder, check out:

It’s an online club for Porsche 550 Spyder enthusiasts. They can tell you all about Porsches of that vintage. And the club is free to join.

Agree, if you want a failure other than the motor, look to the clutch or transmission. In these races you had to shift a lot and the clutch and tranny take a beating.

Perhaps the clutch could be going bad and the driver in a vain effort to stay in the race is “clutchless” shifting and he misses a shift and drops 3rd gear. He can limp into the pits but once the car is stopped he’s done for the day. Since the clutch is relatively easy to fix and you can pull this motor and put in a new transaxle easily. He’s ready to race again in a few hours or the next day. The speed of repair depends on whether the driver is part of the Porsche factory team (fixed in about a half hour) or a struggling financial strapped independant racer (however long you want, based on finding, and buying the parts).

I like the clutch suggestion.

In 1956 racing technology was not what it is today, and race drivers did not have a tractor trailor full of high-speed technicians and spare parts. If they smoked the clutch, a real possibility, they were pretty much through for the day. And a cooked clutch is repairable, so the failure would not be so dramatic as to interfere with the main story line.

A missed shift coming out of a corner, (the shifting in Porsche’s can be somewhat uncertain) the engine over-revs and drops a valve. Plenty of smoke and noise…