[Barnsnake]

I had the same problem. When the ambient temperature was over 85 degrees, the steering would tighten up after about 30 minutes. Let it sit for 15 minutes and it would be perfectly free again. I initially thought it was end-loading due to expansion of the steering shaft near the headers. Loosening a u-joint while it was "sticky" disproved that theory. I went through a lot of steps to isolate the problem, but eventually narrowed it down to the rack itself. I duplicated the problem on the bench with a heat gun to verify that it was not a mounting issue. Nothing to do with lash or lubrication. Whenever the passenger's side mount casting on the rack was over 95 degrees, the rack bushing in that end would sieze, despite ample grease. You could heat the pinion end until it smoked and it still worked fine. It made so little sense I duplicated it two more times to be certain.

After I replaced the rack all was well. I tore the old one completely apart to see if I could determine exactly what was causing the months-long head-scratcher. The rack and the bushing were smooth. No eccentricity or misalignment that I could measure, hot or cold.

I hate unsolved mysteries, but it I know the answer is disassembled on a work bench, and not in my car any more.