A couple of years ago, we publicized the new Stromberg 97 carburetors manufactured by Stromberg Carburetor Ltd. in England (www. stromberg-97.com), which have continued to grow in popularity among fans of these traditional two-barrel carbs. Blundell Speed & Machine, one of the earliest dealers for the new 97s, was an information source for that article. Since then, shop owner Chad Blundell has continued to sell the new carbs and parts (practically all Stromberg 97 components, except for the castings themselves, are available individually), and has also been developing fuel rails and banjo fitting and installing them on customers' cars.
Every time we stopped at the Blundell booth at local shows or dropped by the shop, we got another eyeful of the cool new fittings, which are CNC-machined on the premises. The new banjo fittings can be usedwith hoses, but most of the systems Chad has built for his own customers have used these hard lines, which to our eyes look cleaner without taking away from the traditional appearance.
Blundell has fuel rails for Strombergs on the shelf and ready to ship for most popular intake manifolds. Recently, we finally got the chance to see the assembly of a custom fuel rail system for dual Stromberg 97s on a new Offenhauser intake manifold we picked up at Sacramento Vintage Ford (which will eventually go on the '47 Ford Tudor R&C editor Kevin picked up a while ago). Since Chad hadn't created a system for this specific application yet, this was a custom job that served as a prototype for a new part number. If you have an unusual application, Blundell Speed & Machine can create custom rails based on your specific intake and carb combination. All you have to do is bolt them on.
There are a variety of banjo fittings and related hardware available, including the parts shown here.
These are CNC-machined at Blundell Speed & Machine and are available in polished or satin finish.
A) banjo fitting, 5/16-inch dual line, barbed
B) banjo fitting, U-weld-style single line
C) banjo bolt included with banjo-fitting part numbers
D) banjo fitting, U-weld-style dual line
E) banjo fitting, 5/16-inch single line, barbed
F) crush washers (replacement washers for all fittings)
G) standoff extension to adapt fittings to Holley 94 carburetors
H) stainless steel throttle arms for Strombergs or Holley 94s
One of the problems hot rodders encounter when lining up multiple Strombergs is the potential of starving the carburetor farthest from the fuel pump .Low-restriction fittings help solve that problem. Look closely and you can see that Chad has undercut the inside circumference on the banjo fitting and the shaft on the inlet jet in order to lower restriction. It works. Chad used these parts on an eight-carb, alcohol-fed Chrysler engine for a vintage race car running at Bonneville. Although alcohol requires approximately 20 percent more volume than gasoline, the front carbs were never starved.
You've probably seen this type of early aftermarket brass inlet fitting on Strombergs or Holley 94s (shown). The banjo fitting looks a bit cleaner and can be used on 94s as well as on all Stromberg models. Since the inlet location on the 94s is on the top of the fuel bowl lid instead of out the side, Holley applications require a screw-in standoff extension to locate the banjo fitting past the carburetor's body.
Chad used Steve Eisenhaur's '34 roadster (owned for years by hot rod legend Creighton Hunter) as a test vehicle to develop his first banjo fittings and fuel rails. The Flathead was previously running on two of the four 97s and wasn't drawing enough air due to high compression. The hoses were getting brittle and starting to crack. Chad lowered the compression and opened up all four carburetors. The new fuel lines run from the fuel manifold mounted at the rear with a custom progressive linkage that opens the two middle carbs and then the front and rear carbs. Each is independently sprung. Now the Flathead can keep up with any small-block.
Darrell Greig's '50 Oldsmobile was the second car to use these fittings and rails. Darrell liked the looks of velocity stacks, but he didn't want injection. The Chevy small-block's dual quads were swapped for this six-carb progressive setup using old Strombergs rebuilt with new components. The center two carbs open up during around-town driving, and the outside four serve as secondaries. Each carb runs a U-weld-style single line fitting. Chad built this system using a back bar setup with the fuel manifold in front (in the typical small-block position) and the fuel rails running forward, the opposite of Eisenhaur's Flathead system.
A pair of brand-new Stromberg 97s flow plenty of fuel and air for the Flathead in Matthew Ettinger's '37 roadster, even with the S.Co.T. blower in between. Instead of running separate rails to each carb, as on the previous two examples, Chad used a dual line fitting on the rear carb to keep it cleaner looking and avoid potential space restrictions. Notice the garage door-style spring attached to the rear carb's throttle arm. Chad eliminated the need for this spring, which he demonstrated. Keep reading, and you'll see.
Here's the dual carb and Offenhauser...
Here's the dual carb and Offenhauser manifold system Chad was building for us that will eventually be installed on our '47 Ford project.
Chad modifies the bases by...
Chad modifies the bases by machining the carburetor base where the throttle arm mounts and adding a small torsion spring held in place by a screw.
The throttle arms offered...
The throttle arms offered by Blundell are a better-looking improvement (in our opinion) than the arms shown here.
These rails are built from...
These rails are built from 5/16-inch, 0.035- wall 304 stainless steel tubing. With the Ford Flathead mechanical pump in place, Chad had numerous options for positioning the banjo fitting on the pump and running the line to the U-weld inlet fitting on the first carb.
When he was satisfied with...
When he was satisfied with the way the rail fit, Chad TIG-fused the rails and fittings. He used no welding rod in the process, but he kept the rod handy in case he needed it to fill a hole.
All pieces are pressure-tested...
All pieces are pressure-tested before leaving the shop. Chad tests the parts after they've been polished to make it easier to spot any leaks.
It didn't take long to fabricate...
It didn't take long to fabricate this good-looking twin carb setup. It'll take much less time for customers, who only have to open the box and bolt up the rails and fittings.
As a finishing touch, Chad...
As a finishing touch, Chad swapped the front single line banjo fitting for a double so he could add one of the new fuel pressure gauges he offers through Blundell Speed & Machine.
Here's one more alternative-barbed...
Here's one more alternative-barbed banjo fittings with hose instead of the stainless rails for rodders who prefer that look.