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Old 12-30-2008, 06:48 PM   #5 (permalink)
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Quote:
Originally Posted by NiHaoMike View Post
The main problem with lean burn is overheating. Perhaps water injection can be used to counter that? To check temperatures, could a cheap thermocouple be installed in a hole carefully drilled in the exhaust manifold?
Water injection IS used to counteract overheating in lean conditions... see turbo/Nitrous motors.

Yes, you can use a thermal sensor to check exhaust temps at each cylinder... but that's 4 more gauges to watch, and averaging the temps won't help you, b/c engines are mass produced - no two combustion chambers are the same.

There are things you can do to make it easier to run lean though, if you're rebuilding your engine... one of which is cleaning the cast marks and sharp edges off the piston faces. Fuel/air mixtures prefer a clean (not shiny, but clean) piston face. Same w/ the combustion chamber... you can clean the combustion chamber/valve faces up if you ever do a head gasket... do not attempt to clean the pistons unless you can take them out of the block though.
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