<font face="Verdana, Arial" size="2">Originally posted by Brent: |
No way they had 300hp. I've seen the 91-92 Police 5.7L rated at 195hp and 205hp.</font>
Brent, you are the only one that basically got this right.
1989 LO5 5.7 190 hp
1990 LO5 5.7 190 hp
1991 LO5 5.7 195 hp
1992 LO5 5.7 205 hp
1993 LO5 5.7 205 hp
The above refers ONLY to the 9C1 (police package) LO5. They were all tbi engines. There was also a civilian LO5 available in the Caddy Fleetwood, Buick Roadmaster, and Olds Custom Cruiser, and in model years from 1991-1993, but not consistently for each car type. The Chevy Caprice also got an optional LO5 for 1993 but only in the LTZ Caprice sedan.
The LO3 tbi engines, both civilian and 9C1 models, were rated at 170 fwhp.
For the LO5, the changes in hp (and slight changes in torque, but all were around 290-300 ftlbs @ 2400 rpm) had to do with better flowing cats, lower restriction in the Y-pipe, and a cold air feed to the air cleaner box.... (EDIT: and the L98 "773" cam). There had to be, btw, accompanying changes to the EPROM tables to provide the fuel to match, and hence boost the power slightly.
The LO5 made way for the iron head LT1 5.7 Gen II motor for 1994-1996, and those were ALL rated at 260 fwhp @ 5000 rpm, and 330 ftlbs from roughly 2200-3400 rpm. The LO5 never got rated above 205 hp in the 9C1 Caprice, but I think the trucks used them up to 1995 and they may have been rated at 210 hp. The LO5 was dropped from the trucks for the 1996 model year, which is when the Vortec-head L31 5.7 came out. I think the cam used in that engine was the same cam as in the 94-96 Caprice/Impala LT1.
Most of this info is in Ed Sanow's book "Chevrolet Police Cars 1955-1996". HTH, FYI.
- Ken, '94 LT1 9C1, and Fcar lurker