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Old 02-04-2008, 01:12 PM
oldbogie oldbogie is offline
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Quote:
Originally Posted by curtis73
the 846 cam seems to be a slam dunk with the sniffers in its as-ground LSA. I just wonder what the 110 LSA would do to cruise emissions.
Emissions go up as the LSA gets smaller. But if you're running sequential injection this can be managed by when you inject fuel. Holding off till the overlap is finished will not degrade emissions. But reducing the LSA degrades manifold signal which neither EFI or carbs deal with well. Typically to make up for lost signal the injection or carb is run excessively rich. This isn't good for emissions, mileage, or upper cylinder lubrication but it does improve power a bit.

Typically factory engines are significantly better at emissions than they need to be, because the law put meeting emission standards on the factory for a 100,000 miles without the owner maintaining the motor. You can eat into that cushion with hot rod mods, but then you have to stay on top of the state of tune and the wearing condition of the engine to remain legal.

Bogie
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