Emira weight distribution

[GrahamClark_60-68]

Ok, to preface this noob of the century question I recall the following saying “Better to stay silent and be thought the fool than to speak and remove all doubt.” But after much thought and many Google searches that have come up naught, I’m throwing caution to the wind here.

On weight distribution of the Emira V6 wrt other mid engine cars I understand that the engine positioning which is pretty much over the rear axle rather than more forward of the rear axle puts the car more in the category of “mid-rear” engine rather than “true” mid engine. A quick glance at the specs of the Espirit V8 and Ferrari 308 as a comparison surprisingly (at least to me) shows only slightly more mid bias (2-3%) than the Emira, I’m guessing attributed to the lighter power plant on the Emira. And I do appreciate the extra space I get behind the seats as a result as opposed to these other cars with the seats right up against the firewall.

But…. I’ve always been baffled by the left to right bias of the engine on the Evora and Emira (biased to the right looking from rear of the car). If I didn’t know its origins were British I could chalk it up to the driver being on the left and no passenger (i.e., better balance on the track and for solo driving). But of course for those of you driving on the wrong side of the car and road that would be double trouble (driver and engine on the same side of the car).

I also thought that maybe I was just looking at the supercharger cover and maybe it was offset to the right somehow and the engine itself was actually centered left to right but in the many assembly pictures I’ve seen that doesn’t seem to be the case and it does appear the engine itself is more to the right of the car.

So with this said, yes I’m out of ideas. Can someone help me out with my insanity?

 

[KAR120C]

The transmission is off the shelf as far as dimensions go, so I’m sure they didn’t want to develop a new unit.

 

[me73]

Interesting. I didn’t realize the position of the engine relative to the rear axel was fixed. I assumed you could move the engine forward without moving the rear axel but that they didn’t to save engineering costs. Sounds like there is an engineering constraint.

The transmission determines where the drivetrain mass is relative to the axle. In a front drive car it's beneficial to get the engine as close to the axle as possible for weight distribution and packaging. Unless Lotus was to design a different transmission, they're limited. You can move the relative axle position a little but it starts to effect some behaviors of the car and longevity of the parts.

 

[geoffbland]

Interesting. I didn’t realize the position of the engine relative to the rear axel was fixed. I assumed you could move the engine forward without moving the rear axel but that they didn’t to save engineering costs. Sounds like there is an engineering constraint.

With the engine being mounted transversely, the gearbox is mounted to the side of the engine, on the left-hand side of the car. A half-shaft comes out of the gearbox directly into the left-hand wheel. Another longer half-shaft also comes out of the gearbox travels under the engine to the right hand wheel. I think I have that right, difficult to tell from the service manual as there's no "overall" diagram just smaller detailed ones. Hopefully someone will correct me if I am wrong.
So you may be able tilt the top of the engine forward slightly (might be oiling issues with that) to improve centre of mass. But to move the engine forward without a complete redesign of the transmission you would need some extra linkages to the half-shafts as there would not longer be inline with the gearbox. That would mean extra complexity, more transmission losses and an extra failure point.

It's also worth pointing out that the v6 engine only weights +170KG so around only 12% of the dry weight of the car.