Category Archives: Ringland

Oil Additives: What Subaru Says

Oil Additives: What Subaru Says

Subaru of America does not recommend the use of any engine oil additives in any Subaru engine crankcase. Subaru engines are designed to be lubricated with normal petroleum or synthetic-based engine oils in the viscosity and grade indicated in the Owner’s Manual for each specific engine and usage condition. Subaru has not tested the effectiveness or compatibility of any engine oil additives.

Oil Additive: Avoid adding any oil additives to your Subaru boxer engine.
Oil Additive: Avoid adding any oil additives to your Subaru boxer engine.

However, the use of such oil additives does not void warranty coverage. Usage of any additive is at the owner’s discretion. Since Subaru has not tested the compatibility or effectiveness of any such additives, should an engine failure occur that is determined to be caused by the incompatibility or performance of such an additive, the vehicle owner would be be referred to the additive manufacturer to request reimbursement of the cost of the repair.

If you are using oil additives to try to save a leaking headgasket it’s better to just suck it up and just either install new headgaskets yourself or have the work done by a trusted mechanic.

Either use Subaru’s OEM synthetic motor oil or use Rotella T6 motor oil. If your Subaru is still under warranty by Subaru it’s best to get your oil changed by a Subaru dealership and avoid introducing oil additives into your boxer engine. Even if it’s Subaru’s official stance that they won’t void warranties if oil additives are involved it doesn’t mean that they won’t if there is more evidence of engine “tampering”. Avoid anything that could potentially cause a dealership to refuse service to your car in the future.

Otherwise you might have a expensive repair bill if your Subaru boxer engine spins a bearing or has a ringland failure. Of course adding aftermarket parts like an exhaust or intake along with a tune will greatly increase the justification of a Subaru dealership to void a warranty more than adding oil additives.

Not adding oil additives can be another step in avoiding a void warranty from Subaru of America. On a final note remember that Subaru can scan your ECU for previous tunes even if you went back to a stock tune and will void a warranty for that.

Engine Management For Subaru WRX/STi


Why do I need engine management?


Consider your stock engine management for just a moment. Your stock engine control unit (ECU) is a very complex piece of circuitry that calculates hundreds of variables every second. All of these variables rely on inputs within a + or – range. When you modify your vehicle, these values change. As long as the changes are within the values the ECU expects to receive, your engine runs fine. Once the values are exceeded, the ECU is programmed to compensate to return the values to normal levels.

A typical way of engine management is to use a Cobb Accessport.
A typical way of engine management is to use a Cobb Accessport.

This is a layman’s explanation of how your stock ECU can actually work against you when modifying your vehicle. This also explains why modifications can feel great once they are bolted on but the butt dyno results seem to fade over time. This is due to ECU compensation.

What is the first step in finding what engine management I need? Finding a tuner. The Tuner FAQ will help with the general rules of finding a good tuner. Remember, it’s always better to have a custom tune vs. a plug and play or “staged” map. Always defer to the tuner’s advice as to what to choose as ultimately he will be the one to provide custom support. Discuss your goals and budget and your tuner should set you on the right path. If you are a “plug and play” kind of person, review the options below and decide for yourself along with input from locals in your regional forum and the car parts review forum.

What will engine management do for me? Generally speaking, engine management optimizes several engine functions to create more horsepower and efficiency. The stock ECU is designed to ensure your car runs fine and monitors the engine’s output parameters. Utilizing an aftermarket engine management solution takes this to the next level.

Subaru low compression

Subaru EJ motors are known for having weak ringlands, but when you have over 40 psi difference from cylinder 2 to cylinder 3 I would say the engine is pretty shot.