Fuel Rails for New (and Old) Edelbrock Vintage Manifolds - Improving The Past
From the March, 2012 issue of Street Rodder
By Tim Bernsau
Photography by Gregg Gillaspy
Dimensional Inspection Laboratories...
Dimensional Inspection Laboratories (DIL) uses computer-assisted coordinate measuring machines for dimensional inspection on everything from medical equipment and space shuttle components to computer parts and chocolate bar molds. On this day it was Edelbrock manifolds. Blundell doesn’t need dimensions on the entire manifold, just those that relate to building fuel rails—the relation of the manifold to the fuel fittings, locations of fuel inlets, bolt patterns, carb centers, and surface heights, among other coordinates. In the past, Blundell would have inspected the parts manually, which was time-consuming and less precise. Working with Sean Wertens at DIL, he can now build a three-dimensional model in the computer that he will use to build production tooling, confident that everything is squared, aligned, and dead center and that his customers are getting accurate fuel rail systems that assemble easily and operate smoothly.
Functional art. Nothing under the hood of a hot rod fits that description better than a vintage manifold. In fact, lots of rodders have cool old-time multi-carb manifolds hanging on their walls, strictly for decoration. That makes them art. Let’s talk about making them functional.
Vic Edelbrock Sr. was one of hot rodding’s founding fathers. The company he started in the ’30s has been manufacturing modern and vintage performance parts to the hobby ever since—and the product that started it all was the Edelbrock Slingshot manifold for Flatheads, tested on Edelbrock’s own ’32 roadster on SoCal’s dry lakes.
The latest Edelbrock catalog, containing hundreds of products, still includes the legendary Slingshot manifold. In addition, Edelbrock has re-released several other vintage two-barrel multi-carb intakes for Flatheads, Ford small-blocks, Ford Y-blocks, Chevy small-blocks, and other engine applications.
Over at Blundell Speed & Machine, Chad Blundell has been following this closely. Edelbrock offers carburetors and linkages, but not fuel rails and fittings. Blundell has been developing hard line fuel rails and banjo fittings for early two-barrel carbs like Stromberg 97s, Holley 94s, and Rochester 2GC, as well as new early style two-barrels, like the new Stromberg 97, Demon 98, Speedway Motors’ 9Super7, and the Edelbrock 94. When a customer sends a manifold to Blundell Speed for a custom fuel rail, its dimensions are recorded and kept on file. Eventually Blundell will have dimensions on virtually all popular manifolds, and will be able to build precise rails without needing an actual manifold. Chad Blundell already had the critical dimensions for most of the vintage Edelbrock intakes now being reproduced. The question was, were the dimensions on the new versions identical to the old versions? If not, he would need to develop two fuel line systems for each style of manifold—one for the older version and one for the new version. It was time to do some finding out.
The first step was to convince our connections at Edelbrock to let us borrow some of these new manifolds. Technical sales guy Smitty Smith generously let us borrow the manifolds we needed. They even delivered the parts in person directly to Blundell Speed.
From underneath, the new 3x2...
From underneath, the new 3x2 Flathead manifold is distinguishable from the original SU 359 by the center heat riser passage and a circular notch at the front on the passenger side (lower right in the photo) for the road draft tube in the lifter valley area of the block. When mounted on the engine, it would be hard to tell the new intake from an original.
In every case, the new Edelbrock manifolds looked practically identical to the original versions; so far, so good. But looks can be deceiving. So the next step was to deliver the manifolds, old and new versions, to Sean Wertens at Dimensional Inspection Laboratories (DIL) in Santa Ana, California. The trip to DIL served two purposes: to get scientifically precise dimensions on each manifold and to find out how close the new manifolds are to the originals.
While waiting for DIL to get back to us with the dimensions on the intakes, we went back to Blundell Speed to do a few more eyeball comparisons between some new and original Edelbrock manifolds.
A couple of days later, Chad Blundell called to share the findings from DIL. It was good news. On all of the new Edelbrock vintage manifolds, the dimensions relevant to creating fuel rails, were identical between the new and old versions.
Fuel rails for all of these manifolds, with corresponding carburetor options, are now in stock at Blundell Speed & Machine. For one-off or more elaborate applications, Blundell can design and produce fuel rail systems to order. A “Build Your Custom Fuel Rail Here” prompt on the Blundell Speed website allows customers to order a custom system by using simple menu prompts for brand of carb, number of carbs, type of manifold, inlet style, and other variables. If you’ve got some rare, never-before-seen manifold, Blundell can build a system for that too, but you’ll have to send the manifold so it can be dimensionally inspected for an absolutely correct system (and those dimensions will be stored by Blundell for the next customer with the same rare application).
The do-it-yourselfers among us can order unassembled components to built their own fuel rails, including fittings, tubing, solder, and flux. The Blundell website features a YouTube video, hosted by Chad Blundell, which provides step-by-step instructions for soldering the fuel delivery components and creating a custom configuration.
This 3x2 manifold (PN 1109)...
This 3x2 manifold (PN 1109) is a reissue of Edelbrock’s SU 349 for use on ’49-53 Flatheads. We didn’t have an original available for comparison photo purposes, but as with the 1108 intake, the differences are slight. The 1109 differs from the 1108 earlier Flathead manifold mainly by the two ports in front—a 1-1/4-inch road draft tube port (forward) and a 1-3/8-inch oil fill port. In addition, the rear fuel pump boss is raised compared to the 1108.
Edelbrock’s Triple Deuce manifold...
Edelbrock’s Triple Deuce manifold for ’38-48 Ford Flatheads (PN 1108) is a reproduction of the SU 359. It is designed for use with three-bolt two-barrel carbs. As you can see, there are virtually no visible differences between the original (left) and the new versions. The script logo is the same and even the SU 359 stamping was retained. The configuration and shape of the plenums and runners is also the same. The brand-new finish and “Made in the USA” emblem are the only discernible differences.
Here’s the intake manifold...
Here’s the intake manifold that first put Vic Edelbrock’s name in aluminum. The Slingshot (PN 1103), for use on ’38-48 Flatheads, was Edelbrock’s first product, and is still available. It mounts dual two-barrels (three-bolt Strombergs, Holleys, Demons, and similar carbs) in a Y-design.
The Super Dual (PN 1100) dual...
The Super Dual (PN 1100) dual two-barrel manifold from Edelbrock is for earlier ’38-48 Flatheads applications. With a very different design than the Slingshot, it positions the carbs as far apart as possible. Both the new Slingshot and the new Super Dual are close twins to the older versions, and would be suitable for a period-style hot rod.
Moving forward in time, Edelrock...
Moving forward in time, Edelrock is manufacturing several 3x2 manifolds for ’50s and ’60s Ford engines. Shown here is the Triple Deuce Manifold (PN 5412) for 1962 and later 260/289/302/347 small-blocks. This is a brand-new part for Edelbrock but has the looks of a vintage piece.
Chevy small-block fans (we...
Chevy small-block fans (we know a few) will benefit from Edelbrock’s efforts too. There are a couple of 3x2 manifolds now offered for ’55-86 262-400ci applications. Here we’re looking at the C-357-B Triple Deuce three-bolt carb intake (PN 5418) next to an earlier C-357-B. At first glance there are very few differences between the old and the new, and some of the differences we did find on the old manifold aren’t common to all the older versions. Some changes may have been made sometime in the past. Once again, Edelbrock has kept the distinctive logo and the old part number stampings in the same locations. The temperature gauge and the heater hose locations are the same. Visible differences include a vacuum port on the driver side of the old intake between the front and center carburetors and the spacing of the road draft and oil openings at the front of the part. The new intake has a pair of bosses on the driver side that the old one doesn’t. The old version has a single boss in the back on the same side. Bey
Turning over the 5418, we...
Turning over the 5418, we noticed only one prominent difference, which was the size and shape of the heat crossover passage in the center of the manifold. The new one has some casting details, most noticeably some stampings, including a circular logo at the front. Look for that at the swap meet in 30-40 years to determine whether it’s an original or a 21st century reissue. A similar intake (PN 5419) is for use with four-bolt Rochester 2GC carbs. A third version (PN 5417) fits small-blocks with Vortec cylinder heads.
We love this one. The Edelbrock...
We love this one. The Edelbrock X1 Ram Log (PN 2150) for ’55-86 Chevy 283-327 small-blocks. This is another one of Edelbrock’s early designs. Not as early as the Slingshot, but it goes back to the beginnings of the Chevy small-block in the ’50s. We studied it looking for any slight variation between old and new. The plus-sized runners are the same. The plenums and ports are the same. The logo and the X1 stamping—the same. We would have already known this if we had checked the Edelbrock catalog. Vic Edelbrock Jr. wanted an exact clone of the X1 his father created.
Like Edelbrock manifolds,...
Like Edelbrock manifolds, Blundell banjo fittings and related parts are made in the United States. The CNC-machined and hand-polished fittings are available for use with virtually all vintage-style two-barrel carbs on the market. Fittings and hard lines are made from 0.035-inch 304 stainless steel. The crush washers are 5052 aluminum for a reliable seal. EZ-Solder fittings feature the same 0.035-inch wall thickness as the tubing for better soldering. A) banjo bolt B) crush washers C) stand-off extensions for 94-style carburetors D) banjo fittings, EZ-Solder, dual line E) banjo fittings, EZ-Solder, single line F) banjo fittings, 5/16-inch, hose barb, single line G) banjo fittings, 5/16-inch, hose barb, dual line
The banjo bolts are undercut...
The banjo bolts are undercut on the shaft at the inlet jet for high flow. The inside circumference of the banjo fittings are correspondingly relieved. The inlets have a patented unrestrictive stainless fuel screen inside. It’s not intended as a primary fuel filter, but as secondary protection from particles getting into the needle and seat area of the carburetor. They are held in place by a removable clip and can be cleaned with a shot of air.
The Blundell stand-off extension...
The Blundell stand-off extension is used to adapt the banjo fitting and bolt to Holley 94-style carburetors, which have the fuel inlets on top of the fuel bowl lid.
This computer illustration...
This computer illustration from Blundell Speed illustrates the parallel fuel line style (above) and the in-series style (below).
This is a simple setup: two...
This is a simple setup: two Edelbrock 94 carburetors on an Edelbrock Super Dual Flathead manifold with a mechanical fuel pump, but it shows the clean look of the Blundell fuel rail. This rail system includes 5/16-inch, 0.035-wall 304 stainless steel tubing rails, Blundell EZ-Solder banjo fittings, banjo bolts, and a pair of standoff extensions to adapt the fittings to the fuel inlets on the carbs. The banjo fitting threads are identical to most Flathead fuel pump inlet threads. Whatever your particular application is, you can order rails fully assembled and ready to bolt on, or unassembled.
This parallel line setup,...
This parallel line setup, using six 97s on an old Edelbrock X3 Hemi manifold, is a little more ambitious, but the principle is exactly the same.
Blundell Speed & Machine offers...
Blundell Speed & Machine offers this engine-turned fuel pressure gauge, which suit the looks of the vintage induction systems. They also offer a vintage-looking fuel pressure regulator, engineered to work with the lower pressures of older-style carbs.