SPECIAL FIRING ORDER CAMSHAFTS Tricks for smoother-running, longer crank bearing life, and maybe a few extra horses in the process. by Mike Mavrigian photos by author The cam on the left is a standard firing order bigblock Chevy. The cam on the right is a 4/7 swap cam. Notice that the second and fourth lobes [...]
WE BUILD A VINTAGE FE USING PERFORMANCE AFTERMARKET HEADS, INTAKE, ETC. by Mike Mavrigian all photos by author The “old” Ford 427 FE side oiler has regained its popularity among both racers and street rod/custom car builders, especially for Cobra replica builders. This blast from the past is back with a vengeance.The Ford 427 “side [...]
continued from Part 2 Considering the anticipated forces that a set of rod bolts will encounter during high-performance engine use, it doesn’t make sense to compromise by tightening with torque alone. Two examples of rod bolt stretch gauges. A variety of manufacturers offer these tools. The bottom anvil (stationary pointed pin) is adjustable to accommodate [...]
continued from Part 1 CYCLIC FATIGUE PROTECTION Whether measured by stretch or tightened by torque, rod bolts MUST be installed with the proper amount of preload (bolt stretch) in order to provide proper clamping force. If a rod bolt is installed without sufficient preload, every revolution of the crankshaft will cause a separation between the [...]
MEASURING CONNECTING ROD BOLT STRETCH Optimum bolt preload and clamping force is achieved by monitoring rod bolt stretch as opposed to applying torque value. by Mike Mavrigian photos by author Tightening connecting rod bolts while measuring bolt stretch provides a much more accurate method of achieving proper bolt preload and clamping force. Professional performance and [...]
VINTAGE ENGINE TECH Editor’s Note: This new column is dedicated to providing miscellaneous tidbits of info relative to ever-popular vintage engines that simply refuse to wander off into oblivion. These are the mills that remain dear to our hearts, and that find homes in an array of vehicle applications including nostalgia drags, street rods, old-school [...]
A sample of titanium valves in blank form. Stems have been machined to near-final diameter and the heads are rough formed, prior to CNC machining. Photo courtesy Xceldyne A variety of specialty coatings can be applied to valves to enhance specific properties such as lubricity, resistance to wear and thermal performance. Photo courtesy Xceldyne A [...]
SODIUM-FILLED VALVES Sodium-filled valves feature stems that are precision-gun-drilled and filled with a specially formulated sodium. This achieves weight reduction (the result of the gun-drilling to create a hollow stem) and better heat dispersion. There is some debate concerning the efficiency of this heat transfer due to concerns that the heat transfer to the guides [...]
VALVE MATERIALS AND DESIGNS Choosing the correct valve for specific applications by Mike Mavrigian both photos by author Choosing the optimum valve for a specific application can sometimes be confusing considering the various choices available today. In this article, we attempt to explain the various materials and designs in an effort to better understand today’s [...]
A precision mounting plate is installed to the rear of the block. This accurately locates the block to the machine’s base fixture. A centering bar is inserted through the main bores. The main bore centering bar is bushed to accommodate the specific block’s main bore diameter. A camshaft tunnel centering bar helps the machine to [...]
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