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10/10ths · 03-06-2016, 03:12 PM

....it's not a matter of "modern" oil.

It's all about the piston rings growing as they and the cylinder walls expand as they warm up and start sealing tighter. If you just sit and idle, you get fuel washing past the rings and the fuel gets into the oil. This breaks the oil down over time. The oil then can't protect the engine internals as well.

Remember, the car runs rich on start-up. This dumps extra fuel into the combustion chamber.

You have a flat engine.

The fuel gets by the rings.

By driving off immediately, the engine warms up faster and therefore the piston rings seal up faster and the fuel injection squirts a less rich mixture faster.

You get less fuel in the oil, and your oil does its job of protecting your engine longer, before it needs to be changed.

Just keep her below 3,000 rpm until she's warm.

03-06-2016, 03:12 PM	#15
10/10ths "50 Years of 550 Spyder" Join Date: Jun 2015 Location: The Road Posts: 918	Again... ....it's not a matter of "modern" oil. It's all about the piston rings growing as they and the cylinder walls expand as they warm up and start sealing tighter. If you just sit and idle, you get fuel washing past the rings and the fuel gets into the oil. This breaks the oil down over time. The oil then can't protect the engine internals as well. Remember, the car runs rich on start-up. This dumps extra fuel into the combustion chamber. You have a flat engine. The fuel gets by the rings. By driving off immediately, the engine warms up faster and therefore the piston rings seal up faster and the fuel injection squirts a less rich mixture faster. You get less fuel in the oil, and your oil does its job of protecting your engine longer, before it needs to be changed. Just keep her below 3,000 rpm until she's warm. __________________ 550 SE #310---"It's more fun to drive a slow car fast, than a fast car slow."