Oil changes by time vs miles!

[Randall Paquette <75313.1445@compuserve.com>]

I was wondering if anyone has correlated the engine run time to miles driven in
order to more accurately space intervals of oil changes.  Afterall, a 2000 mile
trip in 3 days doesn't put the same wear on oil as 2000miles in a city (like
Phoenix where its hot, too).

I was thinking - one could install an hour meter once a manufacurer  (Auto or
oil mfg.) specified proper intervals.   You could even get fancier like small
ariplanes - they have a Hobbs meter which counts time whenever the engine is
running, and also a tach based meter that only counts when the engine is above a
certain rpm (so as idle, ie ground/taxi time is not included).

Anyone ever think of doing this are am I just bored.

Randy...

1987 5000CSTQ 193,000mi
1992 VW Passat 78,000mi
1990 V8 80,000mi