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Tune-Up - V8: Engine: Notes

GENERAL SPECIFICATIONS

Engine (1) HP at RPM Torque (Ft. Lbs. at RPM) Compr. Ratio Sore Stroke Displ. Cu. Ins.
326" V8 2-Bbl. 250 at 4600 333 at 2800 9.2-1 3 23/32" 3 3/4" 326
  4-Bbl. 285 at 5000 359 at 3200 10.5-1 3 23/32" 3 3/4" 326
389" V8 2-Bbl. 256 at 4600 388 at 2400 8.6-1 4 1/16" 3 3/4" 389
  2-Bbl. 290 at 4600 418 at 2400 10.5-1 4 1/16" 3 3/4" 389
  4-Bbl. (2) 325 at 4800 429 at 2800 10.5-1 4 1/16" 3 3/4" 389
  4-Bbl. (3) 333 at 5000 429 at 3200 10.5-1 4 1/16" 3 3/4"  
  4-Bbl. (4) 335 at 5000 431 at 3200 10.75-1 4 1/16" 3 3/4"  
  3 Carbs. (4) 360 at 5200 424 at 3600 10.75-1 4 1/16" 3 3/4" 389
421" V8 4-Bbl. 338 at 4600 459 at 2800 10.5-1 4 3/32" 4" 421
  3 Carbs. 356 at 4800 459 at 3200 10.75-1 4 3/32" 4" 421
  3 Carbs. 376 at 5000 461 at 3600 10.75-1 4 3/32" 4" 421
(1) See " Engine Identification  " under TUNE-UP for Code Letters identifying each engine. 
(2) Pontiac only. Automatic Transmission.
(3) Pontiac only. Synchro-mesh.
(4) Tempest GTO only.