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COMP Cams 12-556-4 Nitrous HP Hydraulic Flat Tappet Camshaft 218/230 SBC

(GMC G2500 1979-95, Yukon 1992-95, K1500 1979-86, 1988-99, C1500 1979-86, 1988-99, K2500 1979-86, 1988-95, 1998, Jimmy 1970-91 + 257 more models)

Manufacturer

Picture for manufacturer COMP Cams

Part Number

12-556-4
5 reviews
Sale Price

$309.95

In Stock (7)

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Product Details

The COMP Cams 12-556-4 Nitrous HP camshaft is specifically engineered for small block Chevrolet engines running nitrous oxide systems. This hydraulic flat tappet camshaft delivers aggressive performance with 218°/230° advertised duration, providing the ideal valve timing characteristics to maximize power under nitrous injection while maintaining excellent street manners.

Key Specifications:

  • Advertised Duration: 218° intake / 230° exhaust
  • Duration @ .050": 218° intake / 230° exhaust
  • Valve Lift: .480" intake / .500" exhaust (with 1.5:1 rocker ratio)
  • Lobe Separation Angle: 110°
  • Hydraulic flat tappet design for reliable operation
  • Optimized for nitrous oxide applications

Performance Features:

  • Aggressive duration split maximizes cylinder filling and exhaust scavenging
  • Designed to work with nitrous systems from 100-250 HP
  • Tight lobe separation angle builds cylinder pressure for explosive power
  • Maintains good vacuum for power brakes and street drivability
  • Ideal power range: 1,500-6,000 RPM

This camshaft is designed for small block Chevrolet V8 engines and requires compatible hydraulic flat tappet lifters, pushrods, and valve springs. Professional installation and proper break-in procedures are recommended for optimal performance and longevity.

Products specifications

Fits

GMC G2500 1979-95, Yukon 1992-95, K1500 1979-86, 1988-99, C1500 1979-86, 1988-99, K2500 1979-86, 1988-95, 1998, Jimmy 1970-91, Savana 2500 1996-2002, Savana 1500 1996-2002, C3500 1979-86, 1988-95, K2500 Suburban 1979-86, 1992-95 + 253 more models

Advertised Exhaust Duration

280

Basic Operating RPM Range

1,600-5,900

Grind Number

NX262H

Cam Type

Hydraulic Flat Tappet

Intake Valve Lift

0.462

Camshaft Material

Cast Iron

Cam and Lifter Kit Upgrade

CL12-556-4

K-Kit Upgrade

K12-556-4

Camshaft Series

Nitrous HP

SK-Kit Upgrade

SK12-556-4

Assembly Lubricant Included

Yes

Lifters Included

No

Valve Springs Required

Yes

Lifter Type

Hydraulic Flat Tappet

Prop 65

WARNING: Cancer and Reproductive Harm P65Warnings.ca.gov

C.A.R.B. Exempt for Foreign Vehicles Manufactured Before 1967?

Yes, but must meet tailpipe emission standards for year of vehicle.

C.A.R.B. Exempt for On-Road Vehicles?

No

C.A.R.B. Exempt for Racing and Off-Road Only Vehicles?

Yes, but must be a race/competition only vehicle.

C.A.R.B. Exempt for California Certified Vehicles Manufactured Before 1965?

Yes, but must meet tailpipe emission standards for year of vehicle.

C.A.R.B. Exempt for Federally Certified Vehicles Manufactured Before 1967?

Yes, but must meet tailpipe emission standards for year of vehicle.

Advertised Intake Duration

262

Camshaft Gear Attachment

3-Bolt

LOBE SEPARATION

113

Exhaust Duration at .050 inch Lift

230

Usage

Street/Strip

Exhaust Valve Lift

0.48

Intake Duration at .050 Inch Lift

218

Engine Family

Chevrolet 262-400 c.i. 8 Cylinder (1958-1998)

AMAZON ASIN

B000N5QC22

This part was the cheapest here

Ordering process was smooth and simple.

GREAT PRICES. LOW SHIPPING FEES

What a great company. 1st time buyer and very happy with Price, service, and shipping. Answered emails personally vs. a computer response. A++++ Will buy from in the future.

Fast Easy and backed by Amazon What could be better

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