back in the late 1970s-1980s the more common muscle cars were generally not all that expensive to buy and gas prices were fairly low , but at the time we thought the prices were outrageous. this frequently resulted in guys having sold off the performance cars they now deeply regret selling, but it also resulted in a good selection of cars and engines for the grease monkey gear head crowd to select from, even if the prices were at that time considered high....(IF WE ONLY KNEW , THEN THE PRICES NOW...MOST OF US WOULD HAVE BOUGHT AND STORED SEVERAL AS INVESTMENTS)
but too the point, many of us learned thru trial and error or mistakes the friends made that grabbing the latest cam catalog and just selecting a cam, that was at least 3-5 levels more radical than the stock cam in the car failed too produce the blistering performance we intended to have and eventually , the smarter guys learned from our mistakes.
we eventually learned that you needed the transmission and rear differential gearing and engine compression ratio to be at least a factor in the cam selected and that use of a manual transmission was in general far more forgiving in badly selected component combos that a car with a stock stall speed converter.
now a NOVA or CAMARO,CHEVELLE with a 350 SBC was a very common starting point for building a performance car. back in that time the 2.02/1.60 FUELIE heads and TURBO heads were far more commonly used. by todays standards they are door stops but its still very possible to make a light weight car like a NOVA with a muncie 4 speed destroy the pitifully inadequate traction the tires available and suspensions had.
as a general rule you were not considered to have a serious contender unless you had at least 10.5:1-12:1 compression and a muncie 4 speed with a 3.54:1-4.56:1 rear gear ratio, that MANDATED use of SHELL or SUNOCO high test gas, and a mild flat tappet solid lifter cam. many guys purchased the STOCK Z28 cams as they worked reasonably well on the street, in some cars but were mostly good for providing a lope and rumble in the idle rather that actual performance
notice that the cam specs are a bit too long by todays standards but keep in mind the cams had very gradual ramps to add durability and reduce wear and maintain valve control with fairly mild springs
Standard 302 (30-30) cam, P/N 3849346
Casting #3849347
254 duration @ .050" (intake & exhaust)
.485" lift (with 1.5 rockers)
114 deg. lobe separation
Exhaust Max lift @ 116 deg. BTDC
Intake Max lift @ 112 deg. ATDC
First Design Off-Road cam, P/N 3927140
Casting #3927141
Intake 257 duration @ .050" (333 advertised)
Exh. 269 duration @ .050" (346 advertised)
Lift: .493" intake, .512" exhaust
Intake Max lift @ 108 deg. ATDC
Exhaust Max lift @ 116 deg. BTDC
2nd Design Off-Road cam, P/N 3965754
Casting #3965751
Intake 248 duration (324 advertised)
Exh. 267 duration (334 advertised)
Lift: .512" intake, .535" exhaust
Some of the More Popular Gen I Cast Iron GM Cylinder Heads
http://www.onedirt.com/tech-stories/engine/a-guide-to-vortec-vs-oe-small-block-chevy-heads/
#3767754 – Manufactured from 1959-1961 on 283 Cubic Inch engines. Called the “Power Pack” cylinder heads. 1.72˝ intake valves and 1.50˝ exhaust valves. 60cc Combustion Chambers.
#3774692 – Manufactured from 1958-1964 on 283 Cubic Inch engines. Called the “Power Pack” cylinder heads. 1.72˝ intake valves and 1.50˝ exhaust valves. 60cc Combustion Chambers.
#3795896 – Manufactured from 1963-1965 on 283 Cubic Inch engines. Called the “Power Pack” cylinder heads. 1.72˝ intake valves and 1.50˝ exhaust valves. 60cc Combustion Chambers.
#3782461 – Manufactured from 1964-1966 on 327 Cubic Inch engines. 161/62 cc port volumes, 62cc combustion chamber. Identified by Double Camel hump symbol.
#3782461X – Manufactured from 1960-1963 on 283 and 327 Cubic Inch engines. 172/64 cc port volumes, 62cc combustion chamber. Identified by Double Camel hump symbol.
#3890462 – Manufactured from 1966-1967 on 302, 327, and 350 Cubic Inch engines. 64cc combustion chamber. Identified by Camel hump symbol. No accessory mounting holes.
#3917291 – Manufactured from 1967-1968 on 302, 327, and 350 Cubic Inch engines. 64cc combustion chamber. Identified by Camel hump symbol.
#3932441 – Manufactured from 1969-1970 on 350 Cubic Inch engines. 161-165cc intake port. 76cc combustion chamber.
#3932441X – Manufactured from 1969-1970 on 350 and 400 Cubic Inch engines. 161/65cc ports. 80cc combustion chamber. 1.94″ intake/1.5″ exhaust valves.
#333881 – Manufactured from 1974-1975 on 350 Cubic Inch engines. 76cc combustion chamber. 2.02″ intake/1.6″ Exhaust valves.
#3991492 – Manufactured from 1970 on 350 Cubic Inch engines. Available on the LT1 engine and over the counter. 64cc combustion chamber. Either straight or angled plugs.
one combo we found that worked well was ported fuelie heads
(which BTW don,t always flow as well as VORTEC HEADS with a mild port rework and new springs)
a decent set of headers, a wieand or edelbrock dual plane intake with a 750 holley and a solid lifter cam from ERSON, ISKY, CRANE or general kinetics that had a fairly tight 104-108 LCA and about 228-240 duration, and about .470-.530 lift
but too the point, many of us learned thru trial and error or mistakes the friends made that grabbing the latest cam catalog and just selecting a cam, that was at least 3-5 levels more radical than the stock cam in the car failed too produce the blistering performance we intended to have and eventually , the smarter guys learned from our mistakes.
we eventually learned that you needed the transmission and rear differential gearing and engine compression ratio to be at least a factor in the cam selected and that use of a manual transmission was in general far more forgiving in badly selected component combos that a car with a stock stall speed converter.
now a NOVA or CAMARO,CHEVELLE with a 350 SBC was a very common starting point for building a performance car. back in that time the 2.02/1.60 FUELIE heads and TURBO heads were far more commonly used. by todays standards they are door stops but its still very possible to make a light weight car like a NOVA with a muncie 4 speed destroy the pitifully inadequate traction the tires available and suspensions had.
as a general rule you were not considered to have a serious contender unless you had at least 10.5:1-12:1 compression and a muncie 4 speed with a 3.54:1-4.56:1 rear gear ratio, that MANDATED use of SHELL or SUNOCO high test gas, and a mild flat tappet solid lifter cam. many guys purchased the STOCK Z28 cams as they worked reasonably well on the street, in some cars but were mostly good for providing a lope and rumble in the idle rather that actual performance
notice that the cam specs are a bit too long by todays standards but keep in mind the cams had very gradual ramps to add durability and reduce wear and maintain valve control with fairly mild springs
Standard 302 (30-30) cam, P/N 3849346
Casting #3849347
254 duration @ .050" (intake & exhaust)
.485" lift (with 1.5 rockers)
114 deg. lobe separation
Exhaust Max lift @ 116 deg. BTDC
Intake Max lift @ 112 deg. ATDC
First Design Off-Road cam, P/N 3927140
Casting #3927141
Intake 257 duration @ .050" (333 advertised)
Exh. 269 duration @ .050" (346 advertised)
Lift: .493" intake, .512" exhaust
Intake Max lift @ 108 deg. ATDC
Exhaust Max lift @ 116 deg. BTDC
2nd Design Off-Road cam, P/N 3965754
Casting #3965751
Intake 248 duration (324 advertised)
Exh. 267 duration (334 advertised)
Lift: .512" intake, .535" exhaust
Some of the More Popular Gen I Cast Iron GM Cylinder Heads
http://www.onedirt.com/tech-stories/engine/a-guide-to-vortec-vs-oe-small-block-chevy-heads/
#3767754 – Manufactured from 1959-1961 on 283 Cubic Inch engines. Called the “Power Pack” cylinder heads. 1.72˝ intake valves and 1.50˝ exhaust valves. 60cc Combustion Chambers.
#3774692 – Manufactured from 1958-1964 on 283 Cubic Inch engines. Called the “Power Pack” cylinder heads. 1.72˝ intake valves and 1.50˝ exhaust valves. 60cc Combustion Chambers.
#3795896 – Manufactured from 1963-1965 on 283 Cubic Inch engines. Called the “Power Pack” cylinder heads. 1.72˝ intake valves and 1.50˝ exhaust valves. 60cc Combustion Chambers.
#3782461 – Manufactured from 1964-1966 on 327 Cubic Inch engines. 161/62 cc port volumes, 62cc combustion chamber. Identified by Double Camel hump symbol.
#3782461X – Manufactured from 1960-1963 on 283 and 327 Cubic Inch engines. 172/64 cc port volumes, 62cc combustion chamber. Identified by Double Camel hump symbol.
#3890462 – Manufactured from 1966-1967 on 302, 327, and 350 Cubic Inch engines. 64cc combustion chamber. Identified by Camel hump symbol. No accessory mounting holes.
#3917291 – Manufactured from 1967-1968 on 302, 327, and 350 Cubic Inch engines. 64cc combustion chamber. Identified by Camel hump symbol.
#3932441 – Manufactured from 1969-1970 on 350 Cubic Inch engines. 161-165cc intake port. 76cc combustion chamber.
#3932441X – Manufactured from 1969-1970 on 350 and 400 Cubic Inch engines. 161/65cc ports. 80cc combustion chamber. 1.94″ intake/1.5″ exhaust valves.
#333881 – Manufactured from 1974-1975 on 350 Cubic Inch engines. 76cc combustion chamber. 2.02″ intake/1.6″ Exhaust valves.
#3991492 – Manufactured from 1970 on 350 Cubic Inch engines. Available on the LT1 engine and over the counter. 64cc combustion chamber. Either straight or angled plugs.
one combo we found that worked well was ported fuelie heads
(which BTW don,t always flow as well as VORTEC HEADS with a mild port rework and new springs)
a decent set of headers, a wieand or edelbrock dual plane intake with a 750 holley and a solid lifter cam from ERSON, ISKY, CRANE or general kinetics that had a fairly tight 104-108 LCA and about 228-240 duration, and about .470-.530 lift
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