The following Stock/Super Stock horsepower and index changes, produced by the Automatic Horsepower Factoring System (AHFS), were released August 25. This is the second round of scheduled changes for 2003. All changes will be in effect prior to the Lucas Oil NHRA Nationals in Reading, Pa., and the scheduled Lucas Oil Series event on the weekend of Sept. 12-14. It should be noted that these changes include only results produced by the AHFS.

The AHFS is a simple program based on actual run data compiled from all available runs at NHRA national events only. The data-based format provides the ability to automatically calculate average performances for any class and/or engine combination in Stock and Super Stock. The trigger point for the system is 1.15-second or more and .25-second or less under the respective index. Engine-combination averages and class averages are then computed and analyzed to determine if a change is warranted. The amount of change is calculated on a stepped percentage basis. Where applicable, adjustments will be effective for the specific car model or body style being evaluated. An automatic adjustment is instituted above the three-time a year process when a 1.50 and under is recorded during any NHRA event.

Any comments, thoughts, or requests need to be received in writing and sent to: National Hot Rod Association; Technical Department; attn: AHFS; P.O. Box 5555, Glendora, CA 91740; or e-mail, AHFS@nhra.com.

Stock Horsepower Changes
Engine Yr/Make	CID	OEM HP	NHRA HP	HP Adjustment	New HP	Years Affected
Buick	350	175	260	+4	264	1973-1974 (Apollo)
Cadillac	425	180	240	+3	243	1977-1979
Chevy	134	115	119	+3	122	2000-2002 (truck)
Chevy	283	220	226	+3	229	1964-1966 (Nova, Stick only)
Chevy	305	165-175	253	+4	257	1983-1987 (Camaro)
Chevy	305	215	245	+4	249	1985 (Camaro)
Chevy	350	275-285	325	+5	330	1993-1998 (Camaro, Stick only)
Chevy	327	275	270	+4	274	1966-1968 (Camaro/Nova)
Chevy	402	375	390	+5	395	1970 (Nova)
Dodge	340	275	295	+4	299	1968-1970
Dodge	340	275	310	+4	314	1971 (Demon)
Dodge	360	180	260	+4	264	1980-1981,1983-1985 (truck)
Dodge	360	230-250	260	+4	264	1995-2002 (truck)
Ford	302	235-240	248	+4	252	1993-1995 (Mustang)
Ford	351	266	315	+4	319	1972 (Mustang)
Ford	351	275	330	+5	335	1972 (Mustang, Stick only)
Ford	428	335	375	+5	380	1968-1970 (Mustang)
Plymouth	340	275	295	+4	299	1968-1970
Plymouth	340	275	310	+4	314	1971 (Duster)
Pontiac	305	155-190	253	+4	257	1984,1986-1987 (Firebird)
Pontiac	305	210	245	+4	249	1986 (Firebird)
Pontiac	350	275-285	325	+5	330	1993-1998 (Firebird, Stick only)

Super Stock Index Changes
Class	Current Index	Change	New Index
SS/TD	11.65	-.15	11.50
GT/TD	11.65	-.05	11.60

Super Stock Horsepower Change
Engine Yr/Make	CID	OEM HP	NHRA HP	HP Adjustment	New HP	Years Affected
Buick	307	140	230	+3	233	1981-1988 (GTonly)
Chevy	305	155-175	255	+4	259	1983-1987 (GT only)
Chevy	305	215	238	+3	241	1985 (GT only)
Chevy	307	140	230	+3	233	1986-1987,1990 (GT only)
Chevy	327	250	260	+4	264	1965 (Chevelle)
Chevy	350	275-285	275	+4	279	1993-1998 (SS & GT)
Chevy	400	175	300	+4	304	1975-1976 (GT only)
Chevy	454	215-245	365	+5	370	1973-1976 (GT only)
Dodge	318	175-177	250	+4	254	1985-1988 (GT only)
Ford	289	210	210	+3	213	1964 (Mustang)
Mercury	289	210	220	+3	223	1964 (Stick GT only)
Oldsmobile	307	140	230	+3	233	1983-1990 (GT only)
Plymouth	318	175-177	250	+4	254	1985-1988 (GT only)
Pontiac	305	210	238	+3	241	1986 (GT only)
Pontiac	305	155-190	255	+4	259	1984-1987 (GT only)
Pontiac	307	140	230	+3	233	1981,1989 (GT only)
Pontiac	350	275-285	275	+4	279	1993-1998 (SS & GT)