|1957 283 C.I.-to-1967 327 C.I. Roller Cam Engines
Competition Cams Extreme Solid Lifter Roller Camshafts
1. MECHANICAL ROLLER – Good for weekend cruiser with 9:1 compression, has noticeable idle in smaller engines. Camshaft part number 12-769-8, Camshaft grind number XR68R. Duration at .050, intake 230, exhaust 236, valve lift: intake, .552 and exhaust .564.
2. MECHANICAL ROLLER – Great for power and overall engine torque, very easy on parts. Rough idle in smaller engines, noticeable idle in larger engines. Camshaft part number 12-770-8, Camshaft grind number XR274R. Duration at .050, intake 236, exhaust 242. Valve lift: intake, .564 and exhaust .570.
Required Parts for Proper Engine Assembly Using Stock Valve Covers
1. Crane Cams Gold Race Roller Rocker Arms, 3/8 Rocker Studs, part number 10750-16.
2. Crane Cams Gold Race Roller Rocker Arms, 7/16 Rocker Studs, part number 11752-16.
3. ARP 3/8 Rocker studs, 1.750 tall, part number 134.7101.
4. ARP 7/16 Rocker studs, 1.750 tall, part number 135.7101. Same as Big Block Chevy.
5. Crane Cams Rocker Adjusting Nuts, short style, 3/8, part number 99788-16.
6. Crane Cams Rocker Adjusting Nuts, short style, 7/16, part number 99790-16.
7. Valve Springs, Competition Cams “beehive style”, part number 26120-16.
8. Valve Spring Seats, Competition Cams, part number 46797-16.
9. Valve Spring Retainers, Competition Cams, titanium, part number 794-16.
10. Solid Lifter roller Tappets, Crower Cams, severe duty, part number 66290-H16.
11. Chrome Molly push rods and guide plates are also required.
Recommended Cylinder Heads
1. All stock cylinder heads should be “pocket ported” with subsequent mild porting of the intake and exhaust ports. Heads will require machining for enlarged valve springs screw in rocker arm studs, push rod guide plates and enlarged push rod holes. Recommended valve sizes are 2.02 intake and 1.60 exhaust.
Recommended Exhaust Manifolds
1. Exhaust manifolds should be “port matched” to the cylinder head exhaust ports. The 2 1/2 inch exhaust manifolds that first appeared on 1962, 327 cubic inch engines should be used when and where applicable.
Stroking of 283 and 327 Cubic Inch Engines for Increased Cubic Inches
1. Stroking of 283 and 327 cubic engines is highly recommended for greatly improved horsepower and engine torque. Increasing the stroke of 283 and 327 cubic inch engines is relatively easily done today with readily available aftermarket parts. Aftermarket parts are available from Scat Enterprises, Inc., 1400 Kingsdale Av., Redondo Beach, Ca. 90278. Scat can provide brand new cast or forged crankshafts and forged connecting rods for your particular engine size. Forged or cast aluminum pistons are available from many after market manufacturers.
Comparative Engines Built
1. 283 C.I. engine with 10.00:1 compression in a 1959 C1, close ratio four speed and 4.11 gears and stock Rochester FI. Tremendous increase in power and could run with any 327 C1 or C2 Corvette. This engine was built using camshaft number 1.
2. 283 C.I. engine with 12.00:1 compression in a 1960 C1 vintage race car, very, very expensive engine that produced 441 horsepower on the dyno with a ported and modified Rochester FI Unit. This engine was built using a custom roller camshaft. Refer to Tech Session labeled War Paint in this Web Site for more information on this car.
3. 283 C.I. engine that was stroked to 327 C.I. with 10.00:1 compression in a 1961 C1. This engine produced 347 horsepower on the dyno with a stock Rochester FI Unit. This engine was built using camshaft number 1.
4. 327 C.I. engine that was stroked to 350 C.I., 10.00:1 compression in a 1956 C1. This engine also had ported 2:02 heads and ported 2 1/2 inch exhaust manifolds with a stock Rochester FI Unit. This car had a wide ratio T-10 four speed with 3.55 gears and would go sideways at half throttle in 1st, 2nd and 3rd gear! This engine was built using camshaft number 1.
5. 327 C.I. engine that was factory rated at 365 horsepower. This engine was stroked to 350 C.I. and made an astonishing 456 horsepower with ported cylinder heads and exhaust manifolds using camshaft number 2.
6. 327 C.I. engine that was factory rated at 360 horsepower. This engine is currently in SACC member Vic Preisler’s 1962 Gulf Oil Race Car. The cylinder heads were ported as well as the exhaust manifolds, 11.00:1 compression, stock Rochester FI Unit. This car has a very noticeable idle at 1000 rpm and was built using camshaft number 2.
7. 350 C.I. engine that was stroked to 383 C.I., 10.00:1 compression, stock Rochester FI Unit, AFR aluminum cylinder heads and four tube exhaust headers. This engine produced 453 horsepower at 6200 rpm using camshaft number 2.
Quarter Mile Performance, aka, QMP Racing Engines
Brad Lagman, Owner
9530 Owensmouth Av.
Chatsworth, Ca. 91311