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twin engined cars?
Autoflock Motorsport - 9/5/13 at 11:56 AM

just spotted this on the bay,

I remember tiff diving the z100 twin engined tiger, breaking the world 0-60 recod, then breaking the car lol

In my head I would imagine it to be almost if not impossible to get the engine running totally in sinc. This mini has both the engines linked up to the same axle/drive box, no chain.

Has anone got any experince of thise? is its possible to get them to drive reliably then I would imagin it is a very cheap way of geting a 12k rpm 8 pot 300+bhp powerplant.

Any comments would be great

snakebelly - 9/5/13 at 11:59 AM

Link?

coyoteboy - 9/5/13 at 12:02 PM

They don't have to run totally in sync, you can happily change gear at different times too if you like (within limits). Two people pushing a car makes it easier than one, even if they've got different length legs, they don't have to step perfectly together. All you have to do is ensure neither person pushing the car exceeds their max speed (and thus falls over) or is so feeble they add nothing to the game. think about it this way, all pistons don't produce the same torque even within a normal engine. Too much imbalance and you snap a crank but that's just a design strength issue. Leave them totally separate or link them at the gearbox output, either way they'll work together.

Ultimately I think it's harder to get the full benefit of two engines without massive rotational inertia issues and ending up with a lower power/weight ratio than just one decently tuned engine though.

Do a search, I and others have investigated this a few times and concluded it's not worth the hassle.



[Edited on 9/5/13 by coyoteboy]

Autoflock Motorsport - 9/5/13 at 12:06 PM

twin r1 engine mini | eBay

sorry chaps

Autoflock Motorsport - 9/5/13 at 12:08 PM

quote:
Originally posted by coyoteboy
They don't have to run totally in sync, you can happily change gear at different times too if you like (within limits). Two people pushing a car makes it easier than one, even if they've got different length legs, they don't have to step perfectly together. All you have to do is ensure neither person pushing the car exceeds their max speed (and thus falls over) or is so feeble they add nothing to the game. think about it this way, all pistons don't produce the same torque even within a normal engine. Too much imbalance and you snap a crank but that's just a design strength issue. Leave them totally separate or link them at the gearbox output, either way they'll work together.

Ultimately I think it's harder to get the full benefit of two engines without massive rotational inertia issues and ending up with a lower power/weight ratio than just one decently tuned engine though.

Do a search, I and others have investigated this a few times and concluded it's not worth the hassle.



[Edited on 9/5/13 by coyoteboy]


Cheers for that Coy,

it something I was never considering and never thought about as currently in talks with Holshot on a turbo build for my Dominator, but when I noticed this mini on ebay I thought the engines can be had for 1k each which I thought was very very cheap for the performance.

MikeRJ - 9/5/13 at 12:29 PM

Russ's F1 road car had twin bike engines, each driving it's own rear wheel.

Ultimately an engine is something that provides torque, couple two engines to the same axle and the torque simply adds. In principal this is no different to having an engine with more cylinders, except the torque is combined after the gearbox rather than before.

dhutch - 9/5/13 at 03:21 PM

quote:
Originally posted by coyoteboy
Two people pushing a car makes it easier than one, even if they've got different length legs, they don't have to step perfectly together.

I like that analogy.

Obviously, with both in gear, clutches engauged, there speeds will be fixed together, assuming there in the same gear. But the slightly less powerfull one (be that, its more worn, less well made, variations in throttle possition, etc) will just add slightly less and follow the lead/speed of the other engine.

To be honest, just like the diffrent cyclindered in a multi cylinder engine.

Weird to think about in one way, but totally logical in another.


Daniel

T66 - 9/5/13 at 08:19 PM

The Mini twin R1 uses a Berrisford/autograss drivebox, and these dont have a lsd. The vehicles Ive driven on roads with locked diffs were my Lada/Land Rovers and several 4x4 - 6x6 trucks, and they all wound up pretty quickly.


Apart from single engine running, these cannot be very much use on the road ?