Intended for installation on 1965-1976 Small-Block Oldsmobile 350-403 c.i. engines equipped with a hydraulic roller camshaft, these 356-T6 aluminum casting cylinder heads (#61035) are a modern refinement to our #6051 heads, except they can accommodate a factory-style mechanical fuel pump. A smaller 68 cc combustion chamber achieves a more appropriate small block compression ratio compared to our PN 61025/61029’s larger 77 cc chamber, which yields a lower compression ratio than most engine builders desire on a small block engine. These heads require a 3.9375” minimum bore and feature a modern chamber design with optimized spark plug positioning. Maximum airflow is achieved through the factory 6-degree valve angle using high-flow 200 cc intake and 130 cc exhaust port volumes, along with 2.072” intake and 1.680” exhaust valve sizes in their O.E. positions. A finished deck thickness with added material above the intake port and pre-counterbored head-bolt holes for .5” diameter studs provide extra clamping force in key areas. A stud-and-guide plate valvetrain system (as opposed to the O.E. pedestal type) provides a solid foundation for the beefier diameter pushrods, and Helicoil inserts in the exhaust and rocker stud holes keep bolts secured. However, there are no provisions for a heat crossover.Although these heads will fit on Big-Block Oldsmobile engines, the 68-cc combustion chamber size is not ideal for a big-block application as it will raise compression. See PN61025 and PN61029 for big-block specific cylinder heads.
Installation Instructions


This Part Fits:

Year	Make	Model	Submodel
1975	Buick	Apollo	Base
1975	Buick	Apollo	SR
1975-1976	Buick	Century	Base
1975-1977	Buick	Century	Custom
1976	Buick	Century	Indianapolis 500 Pace Car
1975	Buick	Century	Luxus
1977-1979	Buick	Electra	225
1977-1979	Buick	Electra	Limited
1978-1979	Buick	Electra	Park Avenue
1977-1979	Buick	Estate Wagon	Base
1975,1977-1978	Buick	LeSabre	Base
1975-1978	Buick	LeSabre	Custom
1977	Buick	LeSabre	Custom Sport
1975-1976	Buick	Regal	Base
1976	Buick	Regal	SR
1977-1978	Buick	Riviera	Base
1978	Buick	Riviera	LXXV Anniversary Edition
1975-1976	Buick	Skylark	Base
1976	Buick	Skylark	S
1975-1976	Buick	Skylark	SR
1976	Cadillac	Seville	Base
1975	Chevrolet	Bel Air	Base
1975	Chevrolet	Camaro	Base
1975	Chevrolet	Camaro	LT
1975	Chevrolet	Camaro	RS
1975	Chevrolet	Caprice	Classic
1975	Chevrolet	Caprice	Classic Sport
1975	Chevrolet	El Camino	Base
1975	Chevrolet	El Camino	Classic
1975	Chevrolet	Impala	Base
1975	Chevrolet	Impala	Custom
1975	Chevrolet	Impala	Sport
1975	Chevrolet	Monte Carlo	S
1975	Chevrolet	Nova	Base
1975	Chevrolet	Nova	Custom
1975	Chevrolet	Nova	LN
1975	GMC	Sprint	Base
1975	GMC	Sprint	Classic
1975	GMC	Sprint	High Sierra
1975	GMC	Sprint	SP
1977-1979	Oldsmobile	98	Luxury
1977-1979	Oldsmobile	98	Regency
1977-1979	Oldsmobile	Custom Cruiser	Base
1975	Oldsmobile	Cutlass	442
1968-1975	Oldsmobile	Cutlass	Base
1977	Oldsmobile	Cutlass	Colonnade
1976-1977	Oldsmobile	Cutlass	Colonnade S
1972	Oldsmobile	Cutlass	Cruiser
1968,1971-1977	Oldsmobile	Cutlass	S
1976-1977	Oldsmobile	Cutlass	Vista Cruiser
1975-1977	Oldsmobile	Cutlass Salon	Base
1968-1977	Oldsmobile	Cutlass Supreme	Base
1977	Oldsmobile	Cutlass Supreme	Brougham
1976-1977	Oldsmobile	Cutlass Supreme	Colonnade
1974-1975	Oldsmobile	Cutlass Supreme	Cruiser
1975	Oldsmobile	Cutlass Supreme	Hurst
1976	Oldsmobile	Cutlass Tiara	Base
1968	Oldsmobile	Delmont 88	Base
1968-1979	Oldsmobile	Delta 88	Base
1968	Oldsmobile	Delta 88	Custom
1972-1979	Oldsmobile	Delta 88	Royale
1968-1972	Oldsmobile	F85	Base
1973-1976	Oldsmobile	Omega	Base
1976	Oldsmobile	Omega	Brougham
1976	Oldsmobile	Omega	F85
1975	Oldsmobile	Omega	Salon
1976	Oldsmobile	Omega	SX
1977-1978	Oldsmobile	Toronado	Brougham
1977	Oldsmobile	Toronado	XS
1977-1978	Oldsmobile	Toronado	XSR
1968-1975	Oldsmobile	Vista Cruiser	Base
1977-1979	Pontiac	Bonneville	Base
1977-1979	Pontiac	Bonneville	Brougham
1978-1979	Pontiac	Bonneville	Safari
1977-1978	Pontiac	Catalina	Base
1977-1979	Pontiac	Catalina	Safari
1976-1977	Pontiac	Firebird	Base
1976	Pontiac	Firebird	Esprit
1976-1979	Pontiac	Firebird	Formula
1977-1979	Pontiac	Firebird	Trans Am
1975	Pontiac	Grand Am	Base
1975-1977	Pontiac	Grand LeMans	Base
1977	Pontiac	Grand LeMans	Safari
1976-1977	Pontiac	Grand Prix	Base
1977	Pontiac	Grand Prix	LJ
1977	Pontiac	Grand Prix	SJ
1975-1977	Pontiac	LeMans	Base
1977	Pontiac	LeMans	Safari
1975-1977	Pontiac	LeMans	Sport
1975-1976	Pontiac	Ventura	Base
1975	Pontiac	Ventura	Custom
1975	Pontiac	Ventura	S
1975-1976	Pontiac	Ventura	SJ