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200+hp direct coupling from flywheel to differential - no transmission

200+hp direct coupling from flywheel to differential - no transmission

200+hp direct coupling from flywheel to differential - no transmission

This seems to be uncommon knowledge – little on the Internet.
Sprint cars and dragsters have similar situations.
A simple clutch between the flywheel and differential would be nice but not necessary.
Much Googling has got this in-out box with clutch (maybe not available anymore --history?).
And this "Bert" transmission by Dyno Plus – direct drive unit with clutch.
Are there any other options?   Suppliers?
Can you recommend any engineering level books, reports, papers on similar systems


RE: 200+hp direct coupling from flywheel to differential - no transmission

To clarify a bit:
A sprint car in/out box does not have a clutch, and the supplied vestigial bellhousing does not allow space for one.  The in/out box comprises a lightweight box with a dog clutch.  In use, the dog clutch is engaged, and the sprint car's engine is started, by pushing the car.  The dog clutch stays engaged until it is desired to stop the car.  The dog clutch is disengaged, and the engine runs until its ignition or fuel supply is cut off.  The in/out box provides NO means to get the car moving again.  I don't know whether it's possible to engage the in/out box's dog clutch with the engine moving and the car rolling without fragging the dogs; I'd guess not.

There may be other options.
Diesel engines used for hydraulic drives and such are typically equipped with a multiple output gearbox (see Funk Mfg., owned by Deere), which can optionally have a friction clutch between the engine flywheel and the box proper.  These are typically engaged or disengaged by means of a long manual lever, operating a more or less normal spring engaged clutch and throwout bearing, and equipped with an overcenter spring.  Despite its length, the lever normally requires three men and a boy to operate.  The assembly is typically made of cast iron, and is very heavy, even for a cast iron assembly.  The boxes are typically good for 350HP or so.  The clutches don't like to be engaged at speed like dragster clutches.

Simplest/cheapest way to make an in/out box _with_ clutch, assuming you have the axial room, is to gut a regular manual transmission, e.g. remove the countershaft and some of the associated crap, so you are left with high|neutral.

That's just a WAG; I'm fuzzy on what you actually want to do...

Mike Halloran
Pembroke Pines, FL, USA

RE: 200+hp direct coupling from flywheel to differential - no transmission

FWIW Rover experimented with an 1800cc engine in a mini, and just a fluid flywheel, and reverse or forward in the gearbox. That was 1972 or so.

Advantage was that larger engines don't cost more than smaller engines, compared with gearboxes.

By 1978 the proto was just one of many failed experiments in the carpark.



Greg Locock

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RE: 200+hp direct coupling from flywheel to differential - no transmission

Mike if designed correctly and if rpm is matched close enough to speed a dog clutch can be engaged. That was the principle behind constant mesh truck gearboxes before syncros became common and is the principle behind the dog box style racing transmissions.

Also I know it is not quite the same thing due to the propeller drive, but a dog box in a boat can be engaged at idle with the boat stationary.

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