Choosing the right linkage for your 6×2
So you’ve got yourself a cool 6×2 intake, either a new cast manifold like the Edelbrock X1 ram or the Offenhauser Pacemaker 3924 (low- line), or a U-fab or log-type intake, and you’ve stepped up for six 97s. What you need now is a quality, sturdy linkage that won’t flex when you stick your foot in it, and won’t swamp your beautiful carburetors with huge brackets or weird curved linkage rods going in all sorts of directions (yes, we’ve seen them too).
Stromberg has 6×2 progressive and direct (non-progressive) linkages to fit pretty much everything out there. This means ready-to-fit kits for those popular intakes that are available brand new. And ‘Trim-to-Fit’ kits for everything else.
The direct linkages come complete in one box. The progressive linkages are modular, so you can always get the right parts for your intake. Here’s how they work…
6×2 Direct Linkage.
Let’s get the easy ones out of the way first. Right now, we offer three 6×2 Direct Linkage kits.
Got the Edelbrock X1 ram 6×2 intake?
You need our 9261-D 6×2 Direct Linkage Kit. It spaces the carburetors 4-7/8th inch in front of each other and 9-1/8th inch apart across the intake, and there is no offset between the two banks of carbs. This linkage is ready to go, comes almost completely assembled with the Back-bar levers pinned to the shaft and even though it bolts straight on, it still comes with full instructions, of course.
Got the Offenhauser Pacesetter 3924 6×2 intake?
You need our 9262-D 6×2 Direct Linkage Kit. This is a low-line intake compared with the X1 so it can give you a little more clearance for low hood applications. It spaces the carburetors 4-3/4 inch in front of each other and 6-1/2 inch apart across the intake, with the carbs on the US driver’s side 3/4 inch offset in front of the other bank. As before, this linkage is ready to go.
Got something else?
You need our 9260-D 6×2 Trim-to-Fit Direct Linkage Kit. It will work with intakes that space the carburetors up to 5-1/2 inch in front of each other, up to 9-1/8th inch apart across the intake and up to 1 inch of offset between the two banks of carbs. Believe us, that’s going to cover pretty much every production engine around. How difficult is the trimming? You’ll be drilling and maybe shortening one bracket and adjusting the lengths of the rods. And everything is explained in the Installation Guide included. Download a copy right here in this Tech Center if you’d like to see it first.
Choosing the right 6×2 Progressive kits.
Yes, you need more than one box. A 6×2 progressive linkage is really just two 3×2 progressive kits plus the Back-bar which joins it all together. With so many different variables between intakes, that’s how we offer them. Here’s how to order the right kits for your intake:
1. Measure the carb to carb spacing – from one throttle shaft to the carb in front. Then order TWO Stromberg 3×2 progressive (eg. 9251PRO) linkage kits – one for each bank – to suit your carburetor intake spacing. There’s a list of which linkage fits which spacing below. If your spacing is not covered, buy the next size up and trim down the threaded rod between the secondary (outer) carburetors. Trim the right hand threaded end and add more 3/16-32 UNF thread if required.
For this spacing….use this kit
4-3/4inch………….9253PRO (fits Offenhauser Pacesetter 3924)
4-7/8inch………….9251PRO (fits Edelbrock X1 ram)
2. Now add the 6×2 Back-bar Kit to link both carburetor banks together. 6×2 intakes differ in the space and offset between banks.
For the Edelbrock X1 ram use kit 9261-BB
For the Offenhauser Pacesetter 3924 use kit 9262-BB
For anything else use kit 9260-BB (Trim-to-Fit). It might also pay to compare the spacing, width and offset of the Edelbrock and Offenhauser intakes (see above in Direct Linkages) to see if they are nearer to your requirements.
Your link to the pedal.
Stromberg recommends a mechanical pedal link for all multi-carb systems. Ideally, your 6×2 Back-bar can be connected to the pedal via one of the long levers that work the two banks of carburetors (they have three adjustment/connecting holes at the top). However, if these do not line up with your pedal link, you can add a third long lever to the Back-bar shaft with Stromberg kit 9096K (Long linkage arm/swivel) positioned to align with your throttle pedal ‘pull’ point. There is a lot of spring action in a 6×2 set-up so you might want to consider using a 3/32” roll pin to pin your 9096K lever to the Back-bar to ensure positive location.
As with all our Tech articles, we welcome customer feedback and other input. Email us with your thoughts and if it adds to the debate, we can add it in. …..firstname.lastname@example.org