A 6×2 carb set-up does give you an opportunity to build a very cool solid fuel line of course, where linkage interference is not usually an issue. But if you’re looking for hose-based solutions, it’s not so simple. Firstly, some blower plates put the carbs so close together (side by side) that there is barely room for a hose end or a banjo (see below). And secondly, while direct linkages are usually without issue, progressive linkage present further problems that need special fuel line solutions.
This is why.
On a 6×2 progressive linkage, you must run the sliding progressive rods from the long center carb lever arms to the front carburetors. They cannot join to the back carbs (as you would usually with a 3×2) because of clearance issues with the back-bar. This is a problem with both straight hoses and banjos.
If you use straight hose ends (eg. our 9080K) with hoses to a firewall block or a fuel rail, those sliding rods will rub on the underside of the center carburetor hoses, which you CANNOT allow to happen. And you can’t put them in a lower hole on the center carb lever because you need those for the back-bar link rods. And you can’t swap them because the link rods then hit the BACK carb hoses! But there is a Stromberg solution.
The good news is that we offer a special fitting, 9080K-E, our extended SuperSeat hose fitting, which moves the hose and clamp further out a little to leave a gap for the sliding rod to clear. You may have seen pics of old school 6×2 progressives with slider rods bent like a big L shape to miss that center carb fuel inlet. Use a 9080K-E and bendy rods are history.
So what about banjos? Double trouble. Any 3×2 progressive linkage will hit the banjo line unless you use our 9086K banjo spacers to move the fuel line away from the linkage. So that’s the first requirement. Have you got space between the two banks of carbs to fit banjos on spacers? You need about 1-3/4in gap between the end of the inlet valve (needle & seat) on the one bank and the accelerator pump link rod on the carb opposite. Even then, you still have the same issue as with straight hose ends, where the sliding rod rubs on the underneath of the center carb banjo spacers. And again, we have a solution. 9086K-C has a groove cut in the center to allow that sliding rod free movement. Both 9080K-E and 9086K-C are on our website and available from your friendly Stromberg dealer.
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