Today's Oil and What You Need to Know
Engine oil has had several significant changes in the last ten years and, more importantly, in 2004 a decision was made to reduce the sulfur and the zinc-phosphorus compounds (ZDDP). The ZDDP is used as the primary anti-wear agent for internal engine components. Beginning with the 2004 model of new vehicles, the Federal Government has asked auto manufacturers to warranty catalytic converters for 120,000 miles. Most catalytic converters eventually fail from harmful gases emitted through the exhaust, and two of these are the phosphorous and sulfur which were a prevalent make-up of our older engine oils. All engines will consume some oil through the exhaust. While in most cases this is only a very small amount, the automakers decided it was time to change the chemistry of engine oil rather than adding to the cost of catalytic converters. This change in engine oil has had a significant impact on the performance engine world. Current oils for gasoline engines have the ZDDP compounds reduced by 20% or more. There has been an overwhelming increase in piston scuff and premature ring wear.
If you have purchased a custom-built short-block with forged pistons and a performance ring package, we have taken every precaution to coat the cylinder walls, pistons, and rings with an anti-wear agent. However, it is imperative that you choose engine oil with a significant amount of ZDDP and we require the addition of GM Engine Oil Supplement (EOS) for a minimum of the first 90 minutes, which is provide with your engine. For forged pistons with moly rings or HD steel rings, we suggest an engine oil with a minimum ZDDP content of the following:
Approximate Percentage by Weight
Zinc - 0.120
Phosphorous - 0.115
We recommend Valvoline VR1 Racing Oil 10w-30 and Joe Gibbs Racing Petroleum Break-In Engine Oil.
PCV Systems
The LS-series engines are prone to excessive crank case pressure build-up resulting in oil blow-by, oil consumption, and oil-wetting of the intake manifold. One of the first changes from GM to help resolve this issue was the bay-to-bay "windows" placed in the main webs of the blocks. Any increase in cubic inches places more demand on the PCV system, regardless of the engine type. GM has made several changes to the PCV systems over the years and many consumers have a mismatch of parts and components. It is imperative that you inspect your PCV system and make certain that it functions properly. If you are using a factory PCV system, it is required that you use a new "fixed orifice" PCV valve for routing your pressure relief hose from the valve cover. The GM part number for this item is #12572717. It is also recommended to install breather filters on each valve cover to allow your new stroker engine to properly breathe. These breather filters can be purchased at any local parts store. DO NOT RUN YOUR NEW ENGINE WITHOUT ANY BREATHING SYSTEM INSTALLED! DOING SO CAN DAMAGE YOUR PISTON RINGS AND KEEP THEM FROM SEATING PROPERLY!
Fuel System and Tuning
It is imperative that you make every effort to have your fuel system in proper working order prior to engine start-up. Inspection of the supply lines, return lines, filters, regulators, and proper fuel pressure are the responsibility of the car owner and/or installer. It is extremely critical that you have a PCM calibrated for the correct pressure and injectors before starting the vehicle. Any over-rich condition existing for an extended period of time during the initial start-up will cause piston scuffing, ring wear, and severly hinder the ability for the rings to seat properly and may ruin the engine! It is the responsibility of the owner and/or installer to calibrate the PCM or the carburetor to prevent internal engine damage.
Engine Break-In
Use the correct engine oil! BE SURE TO USE THE GM ENGINE OIL SUPPLEMENT (EOS) THAT IS SUPPLIED WITH YOUR ENGINE FOR INITIAL BREAK-IN! You can add the EOS to any non-synthetic engine oil. We recommend two 45-minute break-in periods allowing ample time between each period for a complete cool-down of the engine. Each period should consist of varied RPM and load with a limit on the RPM of 4500. Avoid extended duration of constant RPM! After the 90-minute period, you should drain the oil and inspect the filter. Replace with a new filter and use one of the recommended oils from the list above or one that you have verified to have the proper amount of ZDDP. It is imperative that you always use oil with sufficient ZDDP for the entire life of the engine! We do not recommend a change to synthetic oil until a minimum of 5,000 miles to ensure proper ring seating.
