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COMP Cams 1678-16 Ultra Pro Magnum 1.8 Ratio Rocker Arm Set for GM LS3

(Chevrolet Silverado 1500 2007-13, Suburban 1500 2007-09, Camaro 2010-16, Corvette 2008-13, Tahoe 2008-09, Avalanche 2007-09, SS 2014-17 + 10 more models)

Manufacturer

Picture for manufacturer COMP Cams

Part Number

1678-16
22 reviews
Sale Price

$556.95

In Stock (10+)

delivery box

Usually delivered within 2 days

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No Hassle Returns

No Hassle Returns

Live-in-stock inventory

Live-in-stock inventory

Fitment guaranteed

Fitment guaranteed

Product Details

The COMP Cams 1678-16 Ultra Pro Magnum rocker arm set delivers precision valve train control for GM LS3 engines with pedestal mount configurations. Engineered with a 1.8:1 rocker ratio, this performance rocker arm set increases valve lift and duration compared to stock rockers, optimizing airflow for enhanced horsepower and torque output.

Key Features:

  • 1.8:1 rocker ratio for increased valve lift and improved engine breathing
  • Ultra Pro Magnum design with needle bearing fulcrum for reduced friction and wear
  • CNC-machined construction from high-strength steel for durability and precision
  • Pedestal mount design for direct fitment on GM LS3 engines
  • Complete set includes all rocker arms needed for engine rebuild or upgrade
  • Self-aligning roller tip reduces valve stem wear and side loading
  • Factory-style mounting configuration for straightforward installation

COMP Cams Ultra Pro Magnum rocker arms are a proven choice for street performance and competition applications where reliability and precision valve train control are critical. The 1.8 ratio provides an excellent balance of increased performance while maintaining proper valve train geometry on LS3 platforms.

Products specifications

Fits

Chevrolet Silverado 1500 2007-13, Suburban 1500 2007-09, Camaro 2010-16, Corvette 2008-13, Tahoe 2008-09, Avalanche 2007-09, SS 2014-17; GMC Yukon XL 1500 2007-14, Sierra 1500 2007-13, Yukon 2007-14, Sierra 2008-16; Hummer H2 2008-09 + 5 more models

Engine Family

LS3 (Factory Offset)

Maximum Valve Spring Open Pressure

850

Rocker Stud Diameter

Pedestal Mount

AMAZON ASIN

B00N6LMJ18

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.

Rocker Arm Material

8650 Chromemoly Steel

Rocker Arm Ratio

1.8

Rocker Arm Series

Ultra Pro Magnum

so far so good!

The delivery time could have been better..

N/A

Easey to place ordered arrived in a timely manner

Hope they wirk

Product delivered late due to weather problems in our area. Product as described online. Price was fair.

Good product. Arrived but it would have been helpful to have a link sent with tracking number to click on. Thanks

Easy

VERY HAPPY WITH THE PRODUCT

This is my 4th autoplicity purchase. I love you guys!!

Thanks

thanks

awsome

The amazon option makes check out a breeze

Website was very easy to navigate.

Very fast service! Excellent product For the price. I WILL Shop here again!

thanks

Excelente..

I'm a first time customer. So far so good. If I should get these two chairs this week i'll be ecstatic!!!!!

awesome

Everything went good, order shipped out the next day. The prices were good but the shipping cost was way to high $25 dollars for 2 head gaskets and some bolts oil pan bolts.

quick and easy

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