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SU HD8 HS8 differences
- Thread starter beez
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Simon TR4a
Jedi Knight
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HS means a "side" float chamber, HD is I think a later model with a diaphragm, HIF means integrated float chamber and is also later than HS. The number tells you the throat size, 4 is 1.5 inch 6 is 1.75 inch 8 is 2 inch.
I think only the 2 inch carbs come in a D version.
Perhaps someone else can confirm this in case my memory is at fault.
Simon.
I think only the 2 inch carbs come in a D version.
Perhaps someone else can confirm this in case my memory is at fault.
Simon.
Hello Adam,
as far as performance and stud fitting to the manifold they are the same.
The essential difference is in the construction around the jet assembly, the HD (D for diaphragm) has the jet totally enclosed within the carburettor body and the diaphragm is there to allow jet adjustment. The HS has the jet assembly protruding from the bottom of the carburettor much like the H type but with a simple tube to collect fuel from the float chamber.
Alec
as far as performance and stud fitting to the manifold they are the same.
The essential difference is in the construction around the jet assembly, the HD (D for diaphragm) has the jet totally enclosed within the carburettor body and the diaphragm is there to allow jet adjustment. The HS has the jet assembly protruding from the bottom of the carburettor much like the H type but with a simple tube to collect fuel from the float chamber.
Alec