my honest opinion is people get way too caught up in displacement as a metric for the ‘size’ of a motor. The only size that matters to me is the physical dimensions and weight.
Thats why you see LS motors in everything, an ohv small block is a small motor imho even though you can do a 511cid with the right block. An 8.1L motor thats maybe 60lbs heavier than the 4.2 and a few inches longer.
I personally think keeping a design from 1955 and evolving it from a carbed, lead burning draft tube polluting dinosaur into the gen V 3v per cylinder, cam-in-cam VVT, direct injection, emissions complient motor is impressive.
All the tech is nice, but the ohv big displacement motor achieves the same goal in a far simpler and cheaper manner.
How much does an LS3 brand new from chevy cost? How much does an RS4 motor that makes less power at peak and far less power throughout the powerband cost?
As far the VE, wait for the gen V motors. Without VVT the LS motors have always been handicapped with baby emissions cams (hence why they make soooo much more power when switching to a 0.620"+ monster). Take away the vvt from the 4.2 and put in a cam that will idle without it and watch the guts get ripped away. My point is, with a well developed vvt system (like the viper v10s vvt) they are going to be able to put in a more aggressive lobe and still have it idle. The 3v will help the revs get higher, smaller valves weigh less for the given area (the 2v flows just fine, its just costly to rev).
For fuel economy, big displacements burn more fuel, but big displacements make more torque at less effort. You can spin a 0.50 gear on a T56 like nothing with a stock ls1 and just sit at 1700rpm cruising on the highway.
The only issue I see with the big displacement is that the big bores required mean long motors, which limits the ability for a fwd based awd system like Audi uses.
Just my honest opinion, not trying to attack anyone.
