Reply to "Big bearing front spindles?"

Doug wrote- "Aluminum on these calipers helps tremendously.
I can't immagine why they ever used the iron Girlings on the race cars to begin with."

It was a 70's/'80s thing. Early aluminum calipers were quite light compared to iron, but nowhere near as stiff. Alloy calipers flexed enough that heavier iron calipers were sometimes retrofitted in race cars to control pad skewing and odd/premature wear patterns. Nowadays with computerized FEA to predict what will happen under race conditions, places that make aluminum race calipers have the best of both: adequate stiffness AND lightness. But 40 yrs ago, not possible.

DeTomasos still sometimes lose front wheel bearings on the street at more-or-less legal speeds, but its usually due to lack of grease and/or service. OEM front wheel bearings are the same p/n as mid-'60s Ford 3/4 ton pickup trucks, so I don't think bearing strength is the issue. I've been on runs where stone-stock Panteras and Mangustas lost front wheel bearings (same part#, BTW), and from a yard away you could smell burned grease. OEM wheel bearing nuts used race-inspired 'staking' to set bearing clearance, and were one-shot-only. At $16 each, most guys tried to get more than one use out of them, often with bad results. Later, Ford/DeTomaso drilled the spindles (and a lot of us did, too) for cotter pins. But the OEM non-castellated nuts didn't allow much tolerance so you needed shim washers. The very late sheet-metal castellation piece with drillings, cotter pins and shim washers helped a little.

A final consideration: for a decade now, I 'borrowed' a successful design and have been scratch-building 'infinitely-adjustable' front wheel-bearing nuts for a few Pantera friends, to allow them to set exactly the wheel bearing clearances they need without drilling, cotter-pins or shims. So far, no failures.