[SFfiredog]

Wilf,
On all modern Ford V-8 engines, the flywheel is not shrouded by the block skirt, it is contained inside the bellhousing. Even if it was, the cast iron of the block would do very little to contain the remains of an exploding flywheel. If you have an aftermarket steel or aluminum flywheel and a premium clutch disc and pressure plate, I would worry more about being hit in the head by a meteorite than have a clutch explosion. Kevlar wraping, like a bullet proof vest is effective at stoping blunt nosed lead (soft) or lead jacketed (still soft) pistol caliber rounds. There have been cases where a person has died from a gunshot wound that never penetrated the vest. There was enough blunt trama to the heart to cause fatal damage. In many cases there is still major injury to the person wearing the vest which include internal bleeding and broken ribs. Imagine an exploding flywheel is like a large caliber armor piercing rifle round. No vest in the world is going to stop a round like that, or keep a ballistic jagged chunk of iron from tearing though it.
In most cases when building a Cobra it will be required to purchase some kind of a bellhousing. If one is planning to do any hot-rodding spend the extra money at the time and purchase a safety bellhousing.
--Mike