Err....the hp only went up by only 3 (185 vs. 188). Torque went up 8 (195 vs 203). Engine block was now aluminum instead of iron, and the compression ratio was bumped up from 9.5:1 to 10.5:1. A lot of the major internals were changed, but driving a '93 and '94 back to back, you will feel virtually no difference whatsoever. Tranny was indeed a slightly revised version of the previous '92-'93 version.
Here is a rundown of changes between '93 and '94, in addition to the mechanical differences above:
- passenger side airbag added
- interior gets an outside temp button
- remote entry gets a 'beep' tone when locking/unlocking, volume adjustment is inside. (the earler models did not beep)
- cfc-free air conditioning system
- Lexus Portable Plus cellular phone becomes optional
- No more manual transmission
Changes between the '94 and '95 models were cosmetic:
- rectangular fogs instead of the round yellow projectors
- revised tail lights
- smoked headlight housings with faint horizontal lines across the lens
So yeah, there is a synopsis of changes withing the gen-1 ES300 production cycle. Its interesting to note that during the gen-2 cycle, Lexus followed a similar pattern. The car debuted in '97, received mechanical changes 2 years afterward in '99 (VVT-i engine, new tranny, etc.), and cosmetic changes the next year, in '00. It will be interesting to see if the gen-3 follows suit. The 3.3 liter engine will debut next year, but cosmetic changes are unknown so far....