Can you upgrade trunnions on your LS rocker arms?
Can you upgrade trunnions on your LS rocker arms?
On the left is a rocker arm with the Comp Cams trunnion upgrade kit installed, on the right a bone stock factory rocker arm. The factory trunnion setup uses a stamped cap to keep the trunnion and bearings in place.
Which is better factory rocker arm or trunnion bushing?
In our opinion, the factory rocker arm is good up to 7,500 rpm, but even there you’re flirting with danger. While our trunnion bushings won’t allow for higher revs, they’re a precautionary upgrade – they improve reliability at the upper end of the stock rev range.
Are there loose needle bearings on a Chevy LS?
There is also a side benefit that there is no chance of any loose needle bearings destroying the engine when using much more aggressive camshaft profiles and severe duty valve springs if a factory rocker bearing fails. Finding needle rollers in the oil pan is, unfortunately, a fairly common sight for many LS owners.
Do you need trunnion bushings for Chevy LS?
While our trunnion bushings won’t allow for higher revs, they’re a precautionary upgrade – they improve reliability at the upper end of the stock rev range. For endurance racing, this is a must. It should be said that even under normal operations, factory needle rollers can fall out.
On the left is a rocker arm with the Comp Cams trunnion upgrade kit installed, on the right a bone stock factory rocker arm. The factory trunnion setup uses a stamped cap to keep the trunnion and bearings in place.
Which is better rocker arm or trunnion Mount?
Sold as a set of 12. (2) Trunnion-mount rocker arms are stronger, stiffer, and lower-friction than traditional ball-and-stud rockers—they’re one of the many things that make GM’s LS engines a popular choice for high-performance builds. So, why would you want to install a rocker arm trunnion upgrade kit?
When do you need to replace rocker arm?
When you install an aggressive camshaft and stiffer valve springs, it only makes sense to consider replacing your rocker arm fulcrums, as well. Fortunately, the experts at Summit Racing Equipment have responded, offering rocker arm trunnion upgrade kits for Chevy’s Gen III/IV LS and Gen V LT engines, as well as the 5.9L 24-valve Cummins diesel.
How are the rocker arms on the LS series secured?
First, a little design history. The valvetrain in the LS series (and next generation LT series) is a net-lash design. This means that the valvetrain is not adjustable from the factory, and each rocker arm is secured to the head by a bolt that when tightened properly, sets the lash/lifter preload to factory spec.
