How big are modern day hemi engines in physical size compared to the Coyote and LS?

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Both the Gen III Hemi and the Coyote are substantially larger up top than LS/LT engines. Bare block dimensions probably aren't too dissimilar, but the Hemi and the DOHC heads are much wider and I'd wager the DOHC heads are taller. It all boils down to valvetrain configuration.

The LS/LT really can't be compared to for a modern V8 when it comes to external dimensions. They're incredibly compact for what they offer, which is why they're so popular for swaps as they'll fit very nearly anywhere you'd want to put them, and despite sticking with the pushrod configuration with two valves per cylinder, they are very much modern engines.

Edit: The LS/LT longblock is up top, followed by the Gen III Hemi and then the Coyote. These pictures should illustrate the primary differences in configuration and explain why they don't really compare.

ls3_afr_heads_1.jpg
HP103-2.jpg
Ford-5.0-coyote.png
 
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And even then the Coyote itself is significantly smaller than the 1960s-big-block the Modular was:

1626544975849-png.1068215
Adding, to stem off confusion, that this comparison is between a Mod and a pre-Mod small block Ford--it looks like a 351W, which has a displacement advantage over even the biggest production Mod V8.

I'm given to understand that Mods actually are bigger than 385-series Ford big blocks, perhaps save for their length along the crankshaft centerline. They are very wide motors and this is the primary concern when you have strut towers to contend with.

Modulars actually rival or nearly rival the Gen II Hemi elephant motors for width at the heads. I posted this comparison previously on this site but can presently find neither the post nor the picture I used.
 
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Found it.
Veering a little bit off-topic, but here are a couple more visual aids.

The second generation Hemi, produced only in the 426ci displacement, earned the nickname "elephant motor" by virtue of its size. This one sits lower than the mod next to it (rather top-heavy with that big Mooneyham), but neither appears to be any closer to the camera lens.

1105sr-15-z-ford-coyote-motor-5-v8-.jpg


And there's a reason the LS is such a popular swap into Miatas, a reason illustrated fairly well here.

Miata-I4-engine-vs-LS3-V8-size-comparison-02.jpg

 
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Both the Gen III Hemi and the Coyote are substantially larger up top than LS/LT engines. Bare block dimensions probably aren't too dissimilar, but the Hemi and the DOHC heads are much wider and I'd wager the DOHC heads are taller. It all boils down to valvetrain configuration.

The LS/LT really can't be compared to for a modern V8 when it comes to external dimensions. They're incredibly compact for what they offer, which is why they're so popular for swaps as they'll fit very nearly anywhere you'd want to put them, and despite sticking with the pushrod configuration with two valves per cylinder, they are very much modern engines.

Edit: The LS/LT longblock is up top, followed by the Gen III Hemi and then the Coyote. These pictures should illustrate the primary differences in configuration and explain why they don't really compare.

ls3_afr_heads_1.jpg
HP103-2.jpg
Ford-5.0-coyote.png
So if the Hemi didn't have hemi heads and if the Coyote didn't have DOHC, would they be similar size to the LS...or at least easier to fit into other cars?
 

The LS using pushrods and a tighter V angle seem to be the reason it saves space, I think he suggests. Would be be otherwise if the other engines utilised them too?

Or is there something inherent in the LS design that makes it better packaging-wise?

I'm responding because I'm interested to know too.
 
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The LS using pushrods and a tighter V angle seem to be the reason it saves space, I think he suggests. Would be be otherwise if the other engines utilised them too?

Or is there something inherent in the LS design that makes it better packaging-wise?

I'm responding because I'm interested to know too.
They're all 90° V angle engines and the Gen III Hemi also uses pushrods.

The Coyote's bare block may be the smallest because its bore centerline is under 4 inches (compared to 4.4 for the LS/LT and 4.46 for the Gen III Hemi) and its deck height is under 9 inches (the Hemi is the tallest at 9.25), but except for engine block length, these are likely to result in fractions of an inch overall differences, and the Coyote's more complex timing gear may mean the assembled Coyote is no shorter in length than the others.

Bare block differences are of very little consequence when it comes to fitment within a chassis, and as already established, the size of the heads is why fitment issues may arise for the Coyote (Gen III Hemi somewhat less so) before the LS/LT.
 
They're all 90° V angle engines and the Gen III Hemi also uses pushrods.

The Coyote's bare block may be the smallest because its bore centerline is under 4 inches (compared to 4.4 for the LS/LT and 4.46 for the Gen III Hemi) and its deck height is under 9 inches (the Hemi is the tallest at 9.25), but except for engine block length, these are likely to result in fractions of an inch overall differences, and the Coyote's more complex timing gear may mean the assembled Coyote is no shorter in length than the others.

Bare block differences are of very little consequence when it comes to fitment within a chassis, and as already established, the size of the heads is why fitment issues may arise for the Coyote (Gen III Hemi somewhat less so) before the LS/LT.
Oh ok, thank you for explaining
 
I always thought it was funny how, back in less enlightened internet days, smug Europhiles would lambast GM for extracting only 500hp from the LS7, an engine with 7 liters of displacement. But I always thought more along the lines of its amazing that GM could cram 7 liters of displacement into an engine scarcely larger than a typical DOHC inline 4.
 
The packaging difference comes at the top of the engine, with the LS having only one row of valves. Even though the Hemi is a pushrod engine, two valves per cylinder, no cams over the head, the heads are still huge by pushing the valves out for the central spark plug location, and thus getting two rows of valves. The heads are as wide (but not as thick) as a DOHC head.
 
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