Not very much like what Smokey was doing.
From what I can work out, Smokey's "Hot Vapour Cycle" used exhaust heat to ensure that a very lean mixture was heated to quite high temperatures, to ensure stable combustion (normally, very lean mixtures have a high percentage of misfires).
Then he used a turbo-charger to increase the pressure of the intake charge to ensure that volumetric efficiency was maintained.
I was mucking around with an on paper concept where hydrocarbons (propane through to iso-octane) were cracked with water, catalyst and heat to form a "water-gas" type process. Get the ratios right, and the fuel and water can be converted to gaseous carbon monoxide and hydrogen.
Turns out that the exhaust energy (heat) can be "looped", returning that heat to the chamber as burnable fuel.
Made some investigations and it's already been patented.