Horsepower on the 421 CID V-8 engines was up – due for the most part to better cylinder heads.  The HO engine now delivered 376 HP and 461 ft. lbs. of torque.

2+2 Option Series 252 –  While not a distinct Series, the car was so unique that we have set it aside as separate model. Coupes and convertibles with this option package had with “421” engine badges on front fenders, “2 + 2” numbering on the hood, rear fenders and deck lid and simulated louvers behind the front wheel cutouts.

Pontiac dropped the “Trophy” name for the V-8s in the 1965 model year however it was the year that the car was fitted with a unique engine called “421 CID “2+2 V-8”.  Standard 2+2 features included heavy-duty springs and shock absorbers, a 3-speed synchromesh manual transmission.  A 4-speed manual unit with a Hurst shifter was optional. Also fitted were dual exhausts and a performance axle ratio of 3.42:1. The new Turbo-Hydramatic 400 automatic transmission replaced the older Hydramatic.

2+2 models were only available as a 2-door hardtop #25237 and as a convertible #25267.

Star Chief – Series 256 – Star Chief models sat on the longer 124.0″ wheelbase. External trim on Star Chief included stylized stars on the rear roof pillar, “Star Chief” in script on the rear fenders and wider chrome moldings along the fin shaped body crease. All features found in Catalinas were standard equipment. Additionally, deluxe wheel discs and steering wheel, electric clock, dual-speed wipers and special upholstery were part of this model line.

Body styles available were the 4-door sedan and the 4-door hardtop sedan.

Bonneville Series 262 – Bonneville identification included “Bonneville”  lettering on the left-hand side of the hood and on the rear fenders, elongated V-shaped badges behind front wheel cutouts, and wide stainless steel accent panels along the lower body under the fin-shaped crease. Bonneville models had rear  fender skirts.

Standard equipment was everything found on Star Chief plus padded instrument panel, front and rear arm rests, padded assist grip, courtesy lamps and cloth and vinyl upholstery combinations. An undetermined number of four-door hardtops had the Brougham option package which Included Pontchartrain cloth and Morrokide upholstery, a Cordova top and ‘Brougham by Fisher’ roof pillar badges.

The Bonneville was available as a 4-door hardtop, and 2-door hardtop, convertible and special long-wheelbase Safari station wagon that carried Bonneville interior trim but was only available as a 6-passenger version.

Grand Prix – Series 266 – The Grand Prix hardtop sports coupe was the most distinctive of all 1965 full-sized Pontiacs. It had an air­ slot grille with a unique, vertically divided, aluminized Insert which incorporated rectan­gular parking lamps. The fin-shaped creases along the lower body were trimmed with a wide stainless steel molding. The letters “GP” were placed on the left-hand lip of the hood, and “Grand Prix” was placed on the front fenders behind the wheel opening. A “GP” badge was placed on the sides of the rear fenders. For the first time, the Grand Prix had rear fender skirts.

Standard equipment included all features found on Bonneville plus monotone Morrokide upholstery and a glove box lamp was also included. Now buyers had a choice of special front bench seat or bucket seats with a console and tachome­ter.

The Grand Prix came in its own special 2-door hardtop body style, #26657.

389 CID 2-Barrel Economy V-8 – Automatic Transmission: Overhead valves. Cast iron block.  Five main bearings.
Displacement: 389 CID.
Bore and stroke: 4.0625″ x 3.750″.
Compression ratio: 8.6:1.
Horsepower: 256 @ 4600.
Torque: 388 @ 2400 RPM.
Valve lifters: Hydraulic.
Camshaft timing: Intake 273°, Exhaust 282°, Overlap 55°, Lift (intake) 0.406″, (exhaust)  0.409″.
Carburetor: Rochester 2GC two-barrel Model 7025060.

NOTE:  Available on All models EXCEPT 2+2 Option.

389 CID 2-Barrel High Compression V-8 – All Transmissions: Overhead valves. Cast iron block. Five main bearings.
Displacement: 389 CID.
Bore and stroke: 4.0625″ x 3.750″.
Compression ratio: 10.5:1.
Horsepower: 290 @ 4600.
Torque: 418 @ 2400 RPM.
Valve Lifters: Hydraulic.
Camshaft timing: Intake 273°, Exhaust 282°, Overlap 55°, Lift (intake) 0.406″, (exhaust) 0.409″.
Carburetor: Rochester 2GC two-barrel Model 7025060.

NOTE: Standard on Catalina and Star Chief Only. Not available others.

389 CID 4-Barrel V-8 – Automatic Transmission Only. Overhead valves. Cast iron block. Five main bearings.
Displacement: 389 CID.
Bore and stroke: 4.0625″ x 3.750″.
Compression ratio: 10.5:1.
Horsepower: 325 @ 4800.
Torque: 429 @ 2800 RPM.
Valve lifters: Hydraulic.
Camshaft duration: Intake 273°, Exhaust 282°, Overlap 55°, Lift: Intake 0.406″, Exhaust 0.409″.
Carburetor: Carter AFB four-barrel Model 3896S.

NOTE:  Standard on Bonneville and Grand Prix. Not Available others.

389 CID 4-Barrel V-8 – Manual Transmission Only. Overhead valves. Cast iron block. Five main bearings.
Displacement: 389 CID.
Bore and stroke: 4.0625″ x 3.750″.
Compression ratio: 10.5:1.
Horsepower: 333 @ 5000.
Torque: 429 @ 3200 RPM.
Valve lifters: Hydraulic.
Camshaft duration: Intake 273°, Exhaust 282°, Overlap 55°, Lift: Intake 0.406″, Exhaust 0.409″.
Carburetor: Carter AFB four-barrel Model 3895S.

NOTE: Standard on Bonneville and Grand Prix. Optional on Catalina and Star Chief. Not Available with 2+2 option.

389 CID Three 2-Barrel V-8 – All Transmissions: Overhead valves. Cast iron block. Five main bearings.
Displacement: 389 CID.
Bore and stroke: 4.0625″ x 3.750″.
Compression ratio: 10.75:1.
Horsepower: 338 @ 4800.
Torque: 433 @ 3600 RPM.
Valve lifters: Hydraulic.
Camshaft duration: Intake 273°, Exhaust 282°, Overlap 55°, Lift: Intake 0.406″, Exhaust 0.409″.
Carburetors: Three Rochester 2-barrel (front) #7024178;  (center AMT) 7025173, (center SMT) 7025175;  (rear AMT) 7024179, (rear SMT( 7025179.

NOTE: Available on all models except 2+2 Option.

421 CID 4-Barrel V-8 – All Transmissions.  Overhead valves. Cast iron block.
Displacement: 421 CID.  Five main bearings.
Bore and stroke: 4.09375 x 4.00″.
Compression ratio: 10.5:1.
Horsepower: 338 @ 4600 RPM.
Torque: 459 @ 2800 RPM.
Valve lifters: Hydraulic.
Camshaft duration: Intake 273°, Exhaust 289°, Overlap 54°, Lift: Intake 0.406″ Exhaust 0.408″.
Carburetor: 4-barrel Rochester Model AFB 3895S (synchromesh), 3898S (automatic).

NOTE: Standard on 2+2 Option, available all others.

421 CID Three 2-Barrel V-8 – All Transmissions. Overhead valves. Cast iron block. Five main bearings.
Displacement: 421 CID.
Bore and stroke: 4.09375 x 4.00″.
Compression ratio: 10.75:1.
Horsepower: 356 @ 4800 RPM.
Torque: 459 @ 3200 RPM.
Valve lifters: Hydraulic.
Camshaft duration: Intake 273°, Exhaust 289°, Overlap 54°, Lift: Intake 0.406″ Exhaust 0.408″.
Carburetors: Three 2-barrel Rochester carburetors: (front) 7024078 (center synchromesh) 7025075 (center Hydra-Matic) 7025074, (rear synchromesh) 7025079 (rear automatic) 7024079.

NOTE: Optional all models. 

421 CID Three 2-Barrel HO V-8 – All Transmissions. Overhead valves. Cast iron block. Five main bearings.
Displacement: 421 CID.
Bore and stroke: 4.09375 x 4.00″.
Compression ratio: 10.75: 1
Horsepower: 376 @ 5000
Torque: 461 @ 3600 RPM.
Valve lifters: Hydraulic.
Camshaft duration: Intake 288°, Exhaust 302°, Overlap 63°, Lift: Intake 0.409″ Exhaust 0.409″.
Carburetors: Three 2-barrel Rochester carburetors: (front) 7024078 (center synchromesh) 7025075 (center Hydra-Matic) 7025074, (rear synchromesh) 7025079 (rear automatic) 7024079.

NOTE: Optional all models. 

NOTE 1: More detailed information on the 1965 389 and 421 CID V8 engines may be found in the 1965 AMA Specifications Sheets. You may access the Full Size sheets HERE.

NOTE 2: All Torque figures are in ft. lbs. unless otherwise noted.