Tools Needed: |
- 8mm socket, 10mm deep socket, socket wrench - 3" socket extension - 10mm gear wrench (HIGHLY recommended, but not absolutely needed) - Flathead screwdriver - Torque wrench |
Parts you will need: |
Parts: - Yella Terra Rockers for LS1 based engines Bolts/gaskets: - POSSIBLY needed for F-body only: 2 AIR tube gaskets GMPN 12553617 Supplies: - Medium strength locktite (optional) |
There are a few reasons one would want to install aftermarket rockers. First, on very rare occasions the stock rocker arms have been known
to fail and spill their roller bearings into the engine. Second, the stock rockers will flex when using stiff springs and you will give up
some of your lift. Third, aftermarket rockers are sometimes adjustable and usually have a roller tip as well as a roller fulcrum (our stock
rockers already have a roller fulcrum). In this document I will detail how to install Yella Terra 1.7:1 ratio LS1 rockers. These rockers were
installed primarily to try to quiet down the valvetrain a little bit and nothing more, however, with the less flex the valve lift should see
about a 20 thousanths increase over a stock LS1 rocker and that may also add a few horsepower to the car. The only caveat to this is that if
you have a car that is on the ragged edge of piston to valve clearance, aftermarket rockers may just push you over the threshold. So, on to some pics of the parts: |
The YT rockers | YT vs. OEM | |
YT vs. OEM | YT's pedestals |
As you can see, this was a pretty painless install. Setting up the initial pair of rockers was really the only trick, and once that is done its easy sailing from there. Go ahead and fire up the car (it should be really noisy for a second, then quiet down) and let it idle. Listen for any abnormal ticking noises that you didn't have before. When we fired up the car, we found the valvetrain to be slightly less noisy than before (the car has a Comp Extreme energy lobed cam in it, so valvetrain noise is an issue), but otherwise idled and drove just like before. Very painless and fun install! Hope you enjoyed it. |