CMI Precision Billet Roller Rocker Arm Kit | Air-Cooled VW Type 1 | 1.5:1 Ratio, DLC Shafts (#E15)

CMI Precision Billet Roller Rocker Arm Kit | Air-Cooled VW Type 1 | 1.5:1 Ratio (#E15)

More rocker ratio means more valve lift from the same cam — and CMI's 1.5:1 billet roller kit delivers it with race-proven hardware. This track-tested assembly features forced-feed oiling and DLC-coated shafts, engineered to survive extreme lift and high RPM while keeping the valvetrain cool. The 1.5:1 ratio is identified by black anodized end caps.

Vehicle Fitment

• VW Type 1 Air-Cooled Engines: Beetle, Bus, Karmann Ghia, Type 3, and Thing — performance and racing builds running high-lift cams. The 1.5:1 ratio increases effective valve lift, so verify rocker geometry, pushrod length, retainer-to-guide clearance, and coil bind for your specific cam and head combination. Not confirmed for Type 4 engines.

Why Choose CMI?

CMI Precision builds this as a track-tested, fully-machined assembly — force-fed oiling and DLC-coated shafts deliver constant cooling and low friction where stamped rockers fail.

Key Features & Benefits

• 1.5:1 Rocker Ratio: Identified by black anodized end caps; increases effective valve lift over a 1.4:1 or stock 1.1:1 rocker.
• Forced-Feed Oiling: Oil routed through the pushrods to the shafts and sprayed onto the roller tips.
• Billet Rocker Arms: Machined from 7050-T651 aluminum, hard-anodized with a Teflon seal.
• DLC-Coated Shafts: 9310 steel shafts with a Diamond-Like Carbon low-friction coating.
• Precision Adjusters: 3/8" H13 tool steel adjusters with ball cups and titanium 12-point lock nuts.
• Grade 12.9 Mounting Studs: With 7075-T651 aluminum blocks and spacers.
• Cooler Running: Constant oil bath cools the valve springs and reduces friction at high RPM.

Technical Specifications

• Ratio: 1.5:1
• Rocker Body: 7050-T651 aluminum, hard anodized
• Shaft: DLC-coated 9310 steel
• Adjusters: H13 tool steel with titanium lock nuts
• Blocks & Spacers: Black anodized 7075-T651 aluminum
• Mounting Studs: Grade 12.9
• Part Number: #E15

Frequently Asked Questions

• What ratio is this kit? 1.5:1, identified by black anodized end caps. The 1.4:1 version has blue caps.
• What does the higher ratio do? It increases effective valve lift over a 1.4:1 or stock 1.1:1 rocker, for more flow from the same cam.
• How does the oiling work? Oil is force-fed through the pushrods to the DLC shafts and sprayed onto the roller tips for constant cooling and low friction.
• Will these fit my build? They fit Type 1 engines; with the added lift, verify geometry, pushrod length, and clearances carefully.
• Is this a CMI product? Yes — CMI Precision, sold by Washburn's Metal.

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WARNING: This product can expose you to chemicals which are known to the State of California to cause cancer and reproductive harm. For more information, go to www.P65Warnings.ca.gov.