justin_o_guy wrote on 12/31/69 at 16:00:06:I used to say things like" That just doesnt make sense"
Now, I have been indictrinated with new words by the PC & sophisticated crowd &^ I say stuff like"well, thats counterintuitive"
But, now that you splained it, I get it, in a kinda sorta way.
Actually, that was a very good analogy of how it works out, and indeed the difference is Low RPM torque vs a high reving engine that will "pull all the way out the back door" (in drag racer terminology) due to it's free flowing design.
Some internal combustion engine science is counter intuitive. I was not really well informed that 2-stroke engines were capable of pulling at low RPMs until I got a Trials bike. The first being a 70s Suzuki RL-250. They make torque (and HP) all the way down to just above idle, by having very different carb/head flow/valving/compression ratio and exhaust tuning, plus spark timing than a higher HP Motocross type bike. But a 2-stroke can indeed pull like a little tractor. They don't all have to go "zing" to pull.
In the case of the LS400, being such an "under square" motor (stroke being much less than bore; and "square" being where bore and stroke are the same) it may need the restriction of smaller intake and exhaust to allow it to produce torque and prevent it from being an all top end and wound up motor. Not what you want on a cruiser style bike. As DrT suggested, this principal only works to the point that the 'restriction' starts to cause power loss instead of more complete combustion through higher intake velocity/swirl etc...