Cast iron block instead of aluminum

[Old Mechanic]

Green Car Congress: New 3-cylinder, 1.0-liter Ford EcoBoost engine to debut in European Focus range

1.0 Ford ecoboost 3 cylinder. Perfect for a Hydraulic Hybrid.

regards
Mech

[Ryland]

unlike the larger EcoBoost engines—cast iron has been selected for the block, reducing the amount of energy needed for warm-up by up to 50% compared with aluminum.

I wonder how the weight of the cast iron block compares to aluminum, I would think that with modern casting and modern alloys that they might not be that heavy, just like steel bike frames can weigh about the same as aluminum because aluminum can not flex very much without cracking.

[Frank Lee]

I like plain ol' cast iron blocks: simple, inexpensive, and cast iron is the best cylinder surface. When done right whatever weight penalty there may be is offset by the benefits.

[oil pan 4]

In the old small block chevy the aluminum version was a full 100lb lighter than the cast iron ones.
The difference between cast iron and aluminum blocks in the newer engines is about 70-80lb.
With 4 cylinder engines I would expect the weight difference between cast iron and aluminum to be about half that.

[Old Mechanic]

It's a 3 cylinder. I think the Kubota D600 was about 135 pounds. Bet this is lighter and cast iron absorbs heat at a much lower rate than aluminum.

regards
Mech

[oil pan 4]

They will produce an aluminum version at some point I bet.
That way they can call it "new" again.

[Daox]

I know the guys up north have problems with keeping their Insights warm in winter. The small aluminum block coupled with oversized grills, low coolant volume and autostop make for coolant temperatures that are all over the place.

[EdKiefer]

With the size of a 3 cylinder 1.0L engine, cast iron would be a lot easier and cheaper with little weight penalty . With aluminum block manufacture cost are a lot more as to get strong block you need to encapsulate the main bearings bridge ,unlike cast iron which is fine with bearing saddles .

Only issue with cast iron block is dissimilar metal one with head being aluminum and rate of expansion being different , possibly head gasket issues down the road .

[Arragonis]

The Aluminium Rover V8 (ex-Buick) is a common conversion for MGB GTs like the one I have, and even in the enlarged 4.6 litre version (original is only 3.5) they weigh less than the original 1.8 B-series boat anchor.

Must get out in the garage some time...

[ConnClark]

The big advantage of cast iron is less heat loss to the coolant as it doesn't conduct heat as well as aluminum. This keeps more heat in the combustion gasses and allows you to extract more power. The down side is it makes it harder to pass Nox emissions.