Martilo,
I can make the hubs from chromoly. I don't because they would be heavier and harder (read more time consuming) to machine. I think material costs are also higher than my current material. This would translate to having to increase the price of the kits. It's already too expensive.
As far as strength, it would be stronger than the aluminum hubs. But you'll run into the law of diminishing returns. The current design of billet amulinum hubs are already way over-engineered. I'm using huge section thicknesses at the mounting face and bearing diameters. These sections are designed considerably larger than even P-car hubs. Also the P-car stuff is cast while my hubs are machined from billet. If these hubs were on the landing gear of a 747, then maybe 4340 would be a better material. For the application, I assure you they are over-designed.
As a side note, I'm working on one kit right now that uses all early 944 rear brakes that are machined for 5-4.5". I machined and studded the 944 hubs, aswell as machined the rotors for the new bolt pattern. This is an option for anyone out there who likes the 944 rear brakes, but not the P-car bolt pattern. I can do any 5-bolt pattern.
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