Fascinating, I've just been reading my Vizard book again.
On page 57 he reminds us that it's not the weight that matters as much as the Rotational Inertia so it's not just how much lighter it is but where the material is removed from.
He also reminds us that one of the downsides of a significantly reduced flywheel inertia is the tickover. Not important on a competition car but I think a road going Morgan should retain some level of refinement in this respect.
On a road car I always think that a smooth tickover is a measure of a well tuned engine.
John07's comment about his 2 stroke kart engines having power curves like needles reminds me of my 100cc International kart engines. Fixed gear, no clutch, no gearbox and it would pull out of a tight hairpin and still rev up to about 12,000 rpm (no rev counter) I.e a very wide torque band but still with good top end. Horses for Courses.
We tuned all our own engines and Cesare Bossaglia was our Tuning Guru with his book, Two Stroke High Performance Engine Design & Tuning.
BTW, Vizard's book was written in 1970 and the 711 engine was released in 1970 it think so he could have been writing about the later engine but more likely the earlier engine as Arwyn suggests..
Last edited by IvorMog; 12/01/20 11:01 AM.
