“Steel–tipped” inlet needles are necessary when using exotic racing fuels or alcohol or when using benzine or acetone additives. A .097" seat size should be used for small four barrel carburetors; a .110" seat size should be used for Carburetors
up to 735 CFM; larger seat sizes should be used with Carburetors
and larger. The following steel inlet needle and seat assemblies are available from Holley.
Inlet Needle Steel Seat Size 0.097 in. Adjustable