If you’re building an engine with a lot of stroke, there’s a good chance you’ll need pistons that include a special oil ring support with the ring package.
That’s because, due to the nature of the piston head design, the oil ring groove interferes with the wrist pin bore. As a result, there’s a small gap in the groove and, if left unchecked, it could allow the oil scraper rings to gradually work loose and pull away from the ring groove.
Suffice it to say, when that happens, you’re going to have a bad day.
That’s why the piston experts over at RaceTec often include a specialized oil ring support with some of their piston kits to prevent that from happening.
Get all the details behind how these oil ring supports work, when and why you’ll need them, and how to install one properly in this quick video we found on the Summit Racing YouTube Channel.
All told, if you’re installing pistons and notice the ring groove intersects with the wrist pin bore, you’ve got to watch this video to avoid a potentially serious issue:
Do the Summit Pro LS forged pistons for the 4” stoke LS’s come with the oil ring support rings? As all 4” stoke LS’s with the 6.125” rods have the piston pins in the ring lands and almost no one makes or uses the stock 5.3-6.0-6.2 length rods as the rod to stroke ratio is bad with them.
Hey Chris, for starters, we recommend reading this article: Summit Racing Makes Choosing a Forged Piston for Your LS Engine Easy!
But as for your question, Summit Racing Pro LS stroker pistons include Groove Lock spacers. They are dimpled and have a slight clamping action to keep them from rotating and fully support the oil ring. In the early days of LS building, high performance engine building, true on-center LS rods weren’t available, but a 6.125 Gen 1 sbc rod was and it used the .927 pin. This became the de facto rod used more than rod ratio being a factor, but the smaller pin nearly offsets the longer length to keep ring lands thick and aids crank counterweight clearance too. Summit Racing’s newest L8T stroker pistons utilize this 6.125/.927 rod as well.
The real secret to the success lies in the carefully designed skirt profiles to keep them from rotating pistons stable at bdc while spreading load equally across the skirt to minimize wear, rock and oiling. With thousands of sets sold, they are a proven solution and instantly adds another 50 ft.-lbs. of torque to any LS engine.