A question

Since flat 12s take up so much same, is it possible to create an inline 12-cylinder engine lying on its side (like a flat 12, only a little more than half the width)?

What about smoothness, structural strength, heat dissipation?

TIA

EDIT: Forgot to mention.. Would it be possible to use a flat crank in such an engine?

An I12? I'm sure it would be one really long engine. I've never heard of any car actually using such an engine. I don't see how it could be smooth either.

Crank and cam torsional vibrations would probably be one of your bigger problems with such an engine. The rest of your concerns would depend on the details of the particular design. I would guess that a cruciform crank would provide smoother operation than a flat one in this application. Why were you particularly interested in using a flat crank? You could certainly fully balance the flat-crank, I12 version, if you wanted to put the effort (and mass) into it. You might have to get "clever" with the torque recoil, though...

What's a cruciform crank? :confused: :confused: :confused:

cross-shaped.

I must admit, I'm not quite visualizing a cruciform crank...

I think the problem here is that not everyone is completely familiar with the basics behind engine firing order, smoothness, and inherent balance. Check here (http://autozine.kyul.net/technical_school/engine/smooth1.htm) for the best online article you'll ever read on the subject (it's several pages long).

Beyond that, I can think of no single advantage an inline 12 has over a V12 other than width, which isn't terribly important in this case. The inline is not at all space efficient, I can't imagine how it'd fit in a modern high performance platform and still leave room for the drivetrain and passenger compartment. And we've already gone over the flat 12 problems, so why exactly aren't you interested in V12's 454Casull?

It's not that I'm not interested in V12s (especially after reading that they were fully balanced :)) I was just interested in exploring the different setups.

:)

Oh OK, cool. Definitely check that link out then, it's a fantastic resource on the basic pros and cons to different engine cylinder configurations IMO.