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Old 03-04-2012, 02:49 PM
L79vette L79vette is offline
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Originally Posted by Valkyrie5.7
I don't claim to be an expert, but I'm sure that I read that the reason why all TBI engines came stock with some sort of swirl function in the intake track (IE in the bowls of the heads on chevys) is because TBI produces such poor atomization?
In comparison to port injection, yes. But TBI atomizes way better than a carburetor, especially at low airflow. Fuel injection does not depend on airflow through the venturi to draw out and atomize the fuel, so the atomization is equally good across the whole range of airflow.

Here is a link to a statement by Jim McFarland, who knows as much about mixture quality as any living human:

Port injection runs at 50-60psi fuel rail pressure, while TBI runs at 12-15psi. Plus with the injector next to and pointed directly at the intake valve, port injection does not give the fuel the opportunity to drop out of suspension while moving through the manifold. So with port injection you can set things up so the fuel evaporates at just the right time.

Last edited by L79vette; 03-04-2012 at 03:00 PM.
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