Question: How to get rid of carbon buildup

[killain]

What's the best way to decarbonize a LS1 ? I get a fair amount of piston slap when the engine is cold and I was wondering if it's due to carbon build up. How damaging is piston slap? I had the fuel injectors cleaned at the dealership last june, but I don't drive it a lot and I use premium fuel 93 octane and I am concerned that since I only have 12K miles on the car the piston slap could cause damage. What do you think?

 

[Mr. Lucky]

"Piston slap" is one of the most frequently blamed problems in LS-based motors. However, in a basically stock motor with normal cylinder wall wear, it is also one of the most frequently misdiagnosed. If you are referring to the valvetrain noise heard for a short time after a cold startup, that is not piston slap. It is normal valvetrain noise, caused by the lousy flow characteristics of the stock oil filter. The stock filter was chosen for its excellent filtration, not its flow rate. Since contaminants in oil are potentially very damaging to an engine (especially a high performance one), it is an excellent strategy on GM's part for minimizing warranty claims. If you are changing your oil and filter at the recommended intervals, such a high filtration filter is unnecessary. In such case, switch to a Baldwin B-31 or K&N filter and the noise will go away. Both filters have excellent flow characteristics and still meet industry standard filtration specs.

As for your question re decarbonizing, just pick up some Sea Foam and follow the directions on the can.