Cam journal or lobe ? The Jalpa cams ride in the aluminum of the actual cam carrier of the cylinder head. There are no “bearings”, unless you enlarge the opening and modify it for needle bearings.

If the lobe is wiped out it is due to improper hardening (courtesy of Lamborghini), or in rare cases a cut-off oil supply; although the cams/lifters can get by with quite a limited oil supply without damage.

Paul