Bridge porting just requires a LOT more grinding than street porting. We do the initial cut for the extra port on the mill, but it can be done with a hand drill. You just need enough to get the rotary files in there and start grinding.
These sample images are of a “J Bridge”. As shown in the images, this type of port requires cutting of the water seal “O” rings, due to the porting done on the rotor housing.
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Finished “J” Bridge port in the side housing. |
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Rotor housing set on side housing – note the cuts needed in the rotor housing to expose the extra port. |
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Somewhat closer view, with light to emphasize the porting. Note how the water seal “O” ring groove has been removed. |
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Very close view of relationship of rotor housing cut to extra port. |
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This shot was taken to show how much earlier the intake port is opening. The rotor is rotating counter clockwise in this view. A street port has not even begun to open yet. |
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With the rotor going counter clockwise, this shows where the rotor is just beginning to close the intake port. |
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Just a view of what the air/gas mixture is traveling toward. |