Good points all around. Where fire is concerned, however, Tiger Foam's “fast rise” insulation is Class 1 fire retardant. So I'm mostly worried about whether or not the engine bay's temperatures reach a level that will damage the foam.
Where engine service is concerned, the engine bay roof (insulated) will pop off. The insulation could also be destroyed, if need be.
think i will use this stuff in an attempt to quiet my bus.
You may want to consider ceramic batt insulation