By Archie Bosman, July 1, 2014, Photography by manufacturer
It’s unrealistic to assume race engines will operate reliably without regular inspections. In fact high-powered high-revving drag racing engines require valve spring pressure checks after each run.
At the other end of the spectrum mild-powered race engines often tolerate at least one season of racing and sometimes two or three before a rebuild is necessary. Despite their admirable longevity, however, you can’t just weld the hood shut and forget them.
“On some high-powered NHRA engines we’ll put three runs on the intake springs and ten or fifteen on the exhaust.”
Chuck Lawrence
Senior engine builder
John Kaase Racing Engines
Valve springs are probably the most highly stressed components in the race engine and most serious racers own a valve spring tester and a spring removal tool. They soon learn that adopting a few simple periodic inspections—often between races—greatly improve the engine’s prospects for survival, reducing the likelihood of premature failure.
Never an arduous job, valve spring pressures can be checked quickly and if replacements are necessary a full set of intake and exhaust valves can be renewed in around 45 minutes. When a spring is broken or its pressure low, replacement is necessary.
“Once valve springs lose about 10 percent of their tension,” says Saturday-night drag racer Mike Knowles, “they need to be changed.” Conveniently, they are replaced with the engine assembled. By applying air pressure to the cylinder via the spark plug hole, the valves are prevented from falling inside. Then the spring removal tool is engaged, the valve locks popped off, the spring changed, the air pressure released and . . . onto the next cylinder.
In addition to replacing broken or worn springs, the valve removal tool is convenient when mating flat tappets to a camshaft. This procedure is usually performed using light break-in springs and followed by the installation of the proper race springs. All of this requires replacing the springs while the cylinder heads are still on the engine.
Available from DRC Race Products, their Valve Spring Removal Tool is designed to perform in-the-car spring removal and replacement easily and economically. The tool is designed to handle the heavy spring pressures of today’s racing engines without the worry of tool flexing or breaking. Manufactured from steel, DRC’s tool is designed to fit aftermarket shaft rocker systems, as well as most Chrysler applications with both aftermarket and stock rockers.
The tool comes complete with one pivot shaft and a removal handle. This allows the tool to be swung out of the way in order to remove the spring without having to remove the tool. Extra shafts are available, allowing the same tool to be used on a variety of engines.
SOURCE
DRC Race Products
10986 Route 235 Dept MGI
Beaver Springs, PA 17812
570-658-3515
www.dracraceproducts.com
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