What I Learned Today — Standard Oil Ring Tension Isn’t Standard

Engine technology is constantly changing and most of the time for the better. Through discussions with Keith Jones and Lake Speed, Jr. from Total Seal, we’ve learned that what were traditionally called standard tension oil rings aren’t “standard” anymore. Total Seal has a machine that can measure the amount of outward force produced by an individual ring like an oil ring. This tension is rated in what is called pound-force (lbf, not to be confused with lb-ft or ft-lbf). This rating is simply the amount of force in pounds exerted outward with the ring installed in the cylinder. This force is not the actual sliding friction, but common sense dictates that a higher pound-force ring tension will result in higher sliding friction numbers.

What’s interesting is that what was considered “standard” tension for an oil ring for a street engine has changed significantly in the last 20 years. If you look at the accompanying chart, you can see that the tension produced by the older 3/16-inch oil rings used in a 1/16-, 1/16-, 3/16-inch ring package is fairly high at 20 lbf. The slightly smaller 3.0mm ring package used in a 2000-era LS1 for example is rated at only 10 lbf.

Oil Ring Tension Chart

Ring Pack Oil Ring Radial Tension Reduction
Standard 3/16-inch 20 lbf   —
Revised Summit GPX 3/16-inch 15 lbf 25%
Standard 3.0 mm 10 lbf 50%

GM engineers realized that this lighter ring tension is still sufficient to control oil in a street engine. Total Seal tells us that tension is not necessarily related to the vertical thickness of a ring package. A 3mm oil ring is 0.117-inch thick while a 3/16-inch ring is 0.1875-inch thick. Total Seal tells us they can create a lower tension in a 3/16-inch oil ring that will help reduce friction and perhaps free up some horsepower while still adequately controlling oil usage for a street engine.

This custom oil ring package can be purchased separately for almost any ring package but we’ve recently run across the GPX ring package from Summit Racing that uses this Total Seal technology for a 1/16-, 1/16-, 3/16-inch ring package that, as our chart indicates, will cut the oil ring tension from 20 lbf to 15-lbf, which is a healthy 25-percent reduction.

Plus, the GPX package also includes a set of gas-ported top rings that should improve ring seal and perhaps add a little power. The combination of the two benefits points to a significant potential gain in power for a typical normally aspirated street engine. Better yet, this GPX ring package is competitively priced, making the decision much easier.

Summit’s GPX package consists of a lateral gas ported top ring combined with a high-quality second ring and a lower-tension oil ring that will work very well in a street engine. The Summit Racing GPX ring packages are available in many popular bore and ring thickness dimensions.

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About the author

Jeff Smith

Jeff Smith, a 35-year veteran of automotive journalism, comes to Power Automedia after serving as the senior technical editor at Car Craft magazine. An Iowa native, Smith served a variety of roles at Car Craft before moving to the senior editor role at Hot Rod and Chevy High Performance, and ultimately returning to Car Craft. An accomplished engine builder and technical expert, he will focus on the tech-heavy content that is the foundation of EngineLabs.
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