4-Pattern 246/256 IB, 248/258 OB Hydraulic Roller Cam for Chevrolet Small Block

SKU
12-475-44
$719.97
  • For Retro-Fit (Link Bar) Hydraulic Roller Lifters; Fits '58-'021 262-400 cid Chevy Small Blocks2
  • .900" Camshaft Base Circle for applications needing additional connecting rod clearance due to "stroker" crankshaft
  • Great in larger c.i. street to street/strip stroker small blocks w/ good heads
  • Upgraded valve train components & aftermarket cylinder heads required

4-PatternOptimize Valve Events Based on Runner Length • Increases Area Under the Curve & High RPM Stability

To make the most power from your engine, you need to optimize the air ingested and captured by avoiding valves closing too soon or too late. Any conventional center layout single throttle body or carbureted V8 intake manifold features longer outboard runners and shorter inboard runners, meaning that each valve event should occur at a different moment.

COMP Cams® 4-Pattern Camshafts are the very first series of cams designed to accommodate this difference in length and avoid valves closing at the wrong times. NASCAR teams have been using camshafts designed this way for years, and using lessons learned along with them, COMP Cams® has designed a series of cams that optimizes valve events and features a large increase in both area under the curve and stability at high RPM.

The camshafts feature four different lobe patterns with one intake and exhaust design for outboard runners, and another intake and exhaust design for the inboard runners. While the four inboard cylinders are all the same grinds, the outboard exhaust openings are two degrees earlier, with outboard intake closings coming two degrees later. This is the first ever use of technology in street vehicles to balance air/fuel ratio per cylinder and can net you a possible 1000+ RPM over other hydraulic rollers and anywhere from 5-20+ horsepower peak to peak, depending on cylinder head flow.

The 4-Pattern hydraulic roller cams are CNC-Machined from steel billet cores with cast iron distributor drive gears. The cams also feature a tight lobe separation for both excellent performance and a throaty sound.

 4-Pattern Vs. Xtreme Energy

1: Cams for '55-'57 engines can be custom ordered. Please Call, Email, Twitter or Live Chat for details.

2: The '87+ Chevy Small Block received provisions for roller lifters. Most '87 - '93 GM cars came with roller lifters, but most '87 - '95 trucks came with flat tappet lifters in roller lifter style blocks. If your block has '87+ OEM-style roller cam provisions but does not have roller components fitted, COMP Hyd. Roller Lifter Install Kit for '87-'90 Blocks or '91-'02 Blocks can be purchased. As well as a '87+ OE-Style COMP Hyd. Roller Cam and '87+ OE-Style COMP Roller Lifters. Pre-'87 blocks require Retro-Fit Link Bar Roller Lifters.

More Information
Make Chevrolet
Engine Family: Chevrolet 262-400 c.i. 8 Cylinder (1958-1998)
RPM Operating Range: 2900-7,200
Grind Number: 299QS10
Cam Type: Hydraulic Roller
Lifter Style: Hydraulic Roller
Camshaft Series: 4-Pattern Small Base Circle
Camshaft Gear Attachment: 3-Bolt
Usage: Street/Strip
Valve Springs Required: Yes
Camshaft Material: Billet Steel
California Proposition 65: WARNING: Cancer and Reproductive Harm P65Warnings.ca.gov
Advertised Inboard Intake Duration: 299
Advertised Inboard Exhaust Duration: 311
Advertised Outboard Intake Duration: 301
Advertised Outboard Exhaust Duration: 313
Inboard Intake Duration at .050 Inch Lift: 246
Inboard Exhaust Duration at .050 Inch Lift: 256
Outboard Intake Duration at .050 Inch Lift: 248
Outboard Exhaust Duration at .050 Inch Lift: 258
Inboard Intake Valve Lift: 0.637
Inboard Exhaust Valve Lift: 0.621
Outboard Intake Valve Lift: 0.637
Outboard Exhaust Valve Lift: 0.621
Lobe Separation: 110.5 OB/109.5 IB
Assembly Lubricant Included: No