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COMP Cams 1678-1 Ultra Pro Magnum 1.8 Ratio Rocker Arms for GM LS3 Pedestal Mount

(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

1678-1
10 reviews
Sale Price

$34.95

4 left at this price

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Usually delivered within 2 days

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Fitment guaranteed

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Product Details

The COMP Cams 1678-1 Ultra Pro Magnum rocker arms are precision-engineered for GM LS3 engines with pedestal mount configurations. Featuring a 1.8:1 rocker ratio, these performance rocker arms increase valve lift over stock 1.7:1 rockers, providing improved airflow and power gains without requiring a camshaft change.

Key Features:

  • 1.8:1 rocker ratio for increased valve lift and performance
  • Ultra Pro Magnum design with needle bearing fulcrum for reduced friction
  • CNC-machined from premium materials for precision and durability
  • Direct fit for GM LS3 pedestal mount applications
  • Trunnion upgrade design eliminates common rocker arm failure points
  • Compatible with factory valve springs up to moderate performance camshafts

These rocker arms are ideal for street performance and mild racing applications where increased lift is desired. The needle bearing fulcrum design reduces friction and wear compared to stock rockers, while the trunnion-style construction provides superior strength and reliability. Installation requires proper valve train geometry checking and adjustment for optimal performance.

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

B00N6LMT8G

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

Cheap

I think having the type of car that the parts match would be alittle more helpful.

excellent service, i had to wait a few days for the order to be processesed, but only because i ordered on Friday afternoon, but love the site!

had a few website issues while trying to process my order.

Great.fast

easy

Ordered Friday and received the shipment Tuesday. Excellent price. The product was exactly as ordered and arrived in good condition. The checkout process at autoplicity.com is incompatible with nonmainstream browsers. No joy even with java, javascript, referrer logging and cookies all enabled. Finally I placed the order over the phone. Ten minutes later I received acknowledgments for two identical orders, 8961 and 8965. I phoned and asked them to cancel one of the duplicate orders. Four hours later I receive an e-mail saying my order 8961 was canceled for one of four possible reasons, none of which was "We canceled your order that was accidentally duplicated." So I had to phone again (phone is more effective with autoplicity than e-mail or chat) to see whether they had canceled one or both orders. The excellent price was offset by the communication hassle. If you prefer not to use IE or Thunderbird or Chrome, then skip the checkout hassle by placing your order by phone.

Can't wait for products to come!

So far so good

Quick shipping. Good info on sttud will definitely irder again

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