The following Stock/Super Stock horsepower and index changes, produced by the Automatic Horsepower Factoring System (AHFS), were released November 24, 2003. This is the third and final round of scheduled changes for 2003. All changes will be in effect beginning Jan. 1, 2004. 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.

Engine Yr/Make	CID	OEM HP	NHRA HP	HP Adjustment	New HP	Years Affected
Buick	231	150	150	+4	154	1978
Buick	350	165	249	+4	253	1975
Buick	403	180-185	284	+4	288	1977-78
Chevy	134	115	122	+2	124	2000-02
Chevy	262	130	155	+4	159	1985
Chevy	305	175-190	245	+4	249	1983-87 (Monte Carlo)
Chevy	305	165-200	257	+6	263	1983-86 (Camaro automatic)
Chevy	327	340	275	+4	279	1962-63 (Corvette stick)
Chevy	346	305-310	339	+5	344	1999-2002 (Camaro)
Chevy	350	200-270	270	+4	274	1971-72 (Nova)
Chevy	350	275-285	330	+5	335	1993-98 (Camaro stick)
Chevy	402	375	395	+5	400	1970 (Nova automatic)
Dodge	340	240	285	+4	289	1972-73 (Challenger)
Dodge	360	230-250	264	+4	268	1995-2002 (truck)
Ford	351	275	335	+5	340	1972 (Mustang stick)
Ford	428	355	390	+5	395	1967 (Shelby)
Ford	429	375	355	+5	360	1971 (Mustang)
Oldsmobile	305	150	235	+3	238	1984 (Cutlass)
Oldsmobile	403	185	284	+4	288	1977-78
Plymouth	340	240	285	+4	289	1972-73 (Barracuda)
Pontiac	305	155-190	257	+6	263	1984, 1986-87 (Firebird automatic)
Pontiac	346	305-310	339	+5	344	1999-2002 (Firebird)
Pontiac	350	275-285	330	+5	335	1993-98 (Firebird stick)
Pontiac	400	180	276	+7	283	1977-78 (Firebird)
Pontiac	403	185	284	+4	288	1977-78

Super Stock Horsepower Change
Engine Yr/Make	CID	OEM HP	NHRA HP	HP Adjustment	New HP	Years Affected
Buick	350	165-170	267	+4	271	1977, 1980 (GT only)
Chevy	305	150-200	255	+4	259	1983-87 (SS only)
Oldsmobile	350	170	267	+4	271	1977-80 (GT only)
Oldsmobile	307	155	220	+3	223	1981-82 (GT only)
Pontiac	305	150-190	255	+4	259	1984-87 (SS only)
Pontiac	350	160-170	267	+4	271	1977-80 (GT only)