3 cylinder engine.

[Jolle]

It would be interesting to see a v3 in the VR6 layout.

What would the advantage be of that? VW had that to make it less wide then a 6L, for power it was less efficient because of the offset in valves.

[Zynerji]

It would be interesting to see a v3 in the VR6 layout.

What would the advantage be of that? VW had that to make it less wide then a 6L, for power it was less efficient because of the offset in valves.

I was t thinking of the super compact block that would give you...

[wuzak]

Could the 3 cyl, or indeed the Nismo shown above, not be mounted transverse and canted forward?

At the moment it isn't permitted by the rules, but it would make the most sense.

No, it isn't allowed in the rules, but we are talking about 3 cylinder engines, which also aren't allowed.

The disadvantage for a transverse engine under the current aerodynamic rules is that you either run a transverse gearbox, or run a longitudinal gearbox with two bevel drives.

The first restricts how much wheelbase you can give your car, unless you use a series of transverse spur gears to fill the gap, and makes it difficult to get the narrow rear end.

In the second case you have an extra power loss through an additional change of direction in the transmission of power. This may be acceptable, if the layout can deliver gains better than the losses in transmission.

[Jolle]

Could the 3 cyl, or indeed the Nismo shown above, not be mounted transverse and canted forward?

At the moment it isn't permitted by the rules, but it would make the most sense.

No, it isn't allowed in the rules, but we are talking about 3 cylinder engines, which also aren't allowed.

The disadvantage for a transverse engine under the current aerodynamic rules is that you either run a transverse gearbox, or run a longitudinal gearbox with two bevel drives.

The first restricts how much wheelbase you can give your car, unless you use a series of transverse spur gears to fill the gap, and makes it difficult to get the narrow rear end.

In the second case you have an extra power loss through an additional change of direction in the transmission of power. This may be acceptable, if the layout can deliver gains better than the losses in transmission.

A transverse gearbox can be very compact, just look at bikes... and a few spurs after each other won’t make that much of a difference. To make it more compact you could do the intake at the front, the exhaust at the back, mount the turbo right there, air box/intercooler on top of the fuel cell...

[roon]

Subjecting a transversely-mounted engine to chassis torsion is seems more problematic than for a traditional longitudinally mounted engine.

[Jolle]

Subjecting a transversely-mounted engine to chassis torsion is seems more problematic than for a traditional longitudinally mounted engine.

With a engine that small and compact, a carbon sub frame wouldn't be a bad idea anyway, transverse or longitudinal. And it wouldn't break the weight bank either.

[roon]

I agree, you could even make the engine non-structure and thus lighter, and pair it with your frame. I bet the weight penalty of a non-stressed engine is not that severe. I've wondered why F1 hasn't gone down this route here in these days of three to four engines per year. A nice, comfy, cushioned and isolated engine within a carbon frame/monocoque.

[Edax]

I agree, you could even make the engine non-structure and thus lighter, and pair it with your frame. I bet the weight penalty of a non-stressed engine is not that severe. I've wondered why F1 hasn't gone down this route here in these days of three to four engines per year. A nice, comfy, cushioned and isolated engine within a carbon frame/monocoque.

If you look at some of the renderings the current Merc f1 engine it looks like they are already diverting some of the loads through a triangular frame.




Same for Honda



As for the shortened distance to the rear. I am wondering what the load distribution at this moment is. In the old days of 1000+ HP I understood they ran 70% rear to gain traction.

[roon]

Correct, but still hard mounted to the chassis and gearbox, moving with them. What I meant to imply was: float the engine on compliant/active mounts as in production cars.

[marmer]

An additional benefit of a lighter engine if not a stress structure less bulk would help with air flow

[Edax]

Correct, but still hard mounted to the chassis and gearbox, moving with them. What I meant to imply was: float the engine on compliant/active mounts as in production cars.

If you're looking for a set of mounting rubbers you will probably not find them. My guess is that with the high g-forces and high torque, you don't want the engine to sway around in every braking/acceleration zone or corner.

What your probably looking for is directional stiffness. You just want enough compliance in certain directions to be able to isolate some movements or vibrations. That means metal.

If you look at the mountings between the honda engine and the frame. If y is the length of the car and z is the height. The bottom ones (between engine and ladder ) are beefed up in the transversal direction supressing rotation and x movement. The top ones with the triangle are stronger in y direction.

The combination will supress most movements except some kind of frame bending or shearing in the yz plane.

That could be by design. Or it could have no meaning at all if the design is overdimensioned. Or it could mean that that movement is not present enough to spend material on.

These kind of things are hard to tell from pictures, but they could already be present in current designs.

[Tommy Cookers]

regarding isolation ie elastomer engine mounts ? - what about the gearbox and final drive and their structural function ?

maybe have the gearbox integral with the engine but the final drive/diff unit (solid mounted) separate and remote
or an integral transverse gearbox and maybe chain or belt drive to the remote diff
(transfer gearing and ratio may make transverse boxes worse in shift performance and/or in weight/bulk but final drive gains)
or 2 chains/belts (1 for each wheel) with the diff integral with the engine/gearbox - as the original Honda S800
or have 2 belt CVT so needing no diff and no gearbox (the DAF) - and active pulley clamping control gives active diff behaviour

fully structural power units started with the H16 BRM, an ideal size and shape
the DFV seemed a bit small for this, but the current units are far smaller and a 3 is tiny

btw c. 100 years ago most car engines were solid mounted, the crankcase providing the front chassis frame torsional stiffness
in essence the rear had no torsional stiffness

[J.A.W.]

This vid may be of thread topic interest, being of a fairly powerful 3cyl engine - on dyno test.

https://www.youtube.com/watch?v=T44ZVTQtLUk