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Chain Diff-Front engine?
tigris - 9/9/08 at 01:08 PM

Does anyone run this setup? The engine would be pushed as far back as possible, and offset into the passenger footwell to minimize chain length. My reasoning for doing this would be to get rid of the prop/diff housing. My lightest option on a shaft diff is a subaru unit stateside, weighing around 30 kg, I can do a chain diff setup, and integrate a brake rotor to shave quite a bit of unsprung weight.

Aico - 9/9/08 at 01:30 PM

I never saw it, but I guess it's possible. Howlong would the distance be? Also do you have enough room for the engine to sit transverse? Or do you have another way to fit the chain?

russbost - 9/9/08 at 01:41 PM

Surely with a transverse lump driving a chain to the front end you'd have 6 reverse gears (as fitted to Italian tanks in WW2)

Mr Whippy - 9/9/08 at 01:46 PM

even still that sounds quite a lot of chain, how are you going to constrain it from flapping around. Maybe tensioned plastic guide wheels? Wonder too how much snatch you'd get once the chain becomes worn, I have a big cement mixer that suffers from that, the chain gets quite a beating form the shock loads and one day it's going to snap.

tigris - 9/9/08 at 01:46 PM

About 1.3 meters or so, front engine driving rear wheels, much like the configuration in a bike, or many mid engine setups, just a longer chain

Mr Whippy - 9/9/08 at 02:01 PM

quote:
Originally posted by tigris
About 1.3 meters or so, front engine driving rear wheels, much like the configuration in a bike, or many mid engine setups, just a longer chain


hmm ok so long as you think 1.3m it isn't excessively long, sounds almost twice the distance of a bike chain, draw it out full size on a piece of paper and imagine it flying around at a few thousand rpm and kind of flapping about too

[Edited on 9/9/08 by Mr Whippy]

nick205 - 9/9/08 at 02:08 PM

What about 2 separate chains with an intermediate set of sprockets?

You could even fine tune the gearbox to final drive ratio then with different size sprockets

JoelP - 9/9/08 at 02:16 PM

dp's prototype used chains in a similar fashion, LHD with the engine in the passanger seat, with chains going front and back to make AWD. Think he's going onto drive belts to reduce splatter, chatter and matter (weight ).

Nylon guides would help somewhat




http://www.dpcars.net

Mr Whippy - 9/9/08 at 02:19 PM

blimey what a cool toy that is ^ looks like a big r/c car!


quote:
Originally posted by nick205
What about 2 separate chains with an intermediate set of sprockets?

You could even fine tune the gearbox to final drive ratio then with different size sprockets


cool idea and easy to do, just need a key'd shaft or even simply bolt the two sprockets togeather with a thin spacer inbetween.

[Edited on 9/9/08 by Mr Whippy]

WanchaiWarrior - 9/9/08 at 11:56 PM

quote:
Originally posted by Mr Whippy
blimey what a cool toy that is ^ looks like a big r/c car!


Yeah its a pretty neat car, in fact thats unfar, its very neat, his website is HERE