Intake Manifolds

Please note that this page is still under construction!

---

One of the most common decisions one faces when running a Y Block is what sort of induction system to use. Some new parts are available, and many swap meets and ebay auctions list older used parts that hold appeal to many. For instance, those who are looking at maximum power for today’s Y Block would first look to the new “Blue Thunder” single 4v intake, or perhaps a reworked 1957 4v Ford manifold. The single plane 4v manifold offered by Jerry Christensen offers drag strip proven performance. Homemade intakes are also a possibility here and some Y Block users have fabricated tunnel rams with some success.

Others are not as performance oriented, but instead tend toward the novelty and nostalgia of the classic triple-deuce or 3x2 setup, with either a trio of Strombergs or Chandler-Groves/Ford/Holley carburetors. (More on carburetors further later on this page.) Beyond this, there are other possibilities that you might choose for your Y Block, some of which will be covered in this discussion.

---

	Blue Thunder This is probably the best bet for a Y Block performance manifold. Its flow and power production have been proven in dyno tests. The profile of the manifold is low for hood clearance.
	Ford ECZ 9425 B This manifold is an old favorite of Y Blockers. It can be modified and flows well, even in stock form. It will accept modern Holley, Carter, and Edelbrock carbs. It came on 1957 Fords and Mercs, also some ’58 Mercs. Also check out large truck engines, some of which came with a similar manifold.
	Modified ECZ 9425 B This individual has use a fair amount of ingenuity to modify the stock Ford manifold. In order to gain access to all of the runners, especially the transition points, he has machined the top of the manifold, opened the runners, and then fitted an aluminum plate to the flat surface. In my opinion, one probably could come near the flow results of this effort with a new Blue Thunder manifold, which would then have increases available through porting beyond what the stock casting could support. However, this might be a reasonable way to mount a Rootes-type blower, such as a 4-71.
	Ford ECZ 9425A This manifold is used on 55 and 56 Fords and Mercurys and uses the Holley “Teapot” Model 4000 carburetor. It can be recognized by the small 4v mounting flange. This manifold is best suited to the smaller ported 55 and 56 heads. An adapter must be used to mount a modern Holley or AFB 4v carburetor.
	Edelbrock F548 I have not had a chance to examine this manifold personally, but it appears to mate a small flange “Teapot” type Holley to small port heads of ’54 Y Blocks.
	Ford EDB 9425C Ford brought out this manifold as part of a dual quad kit that could be purchased from the dealer over the counter in 1956. Its ports match for 55 and 56 style heads. Note how the back carb mounting pad is centered over the rear port runners and not moved ahead, as in the ’57 manifold below. This manifold was made for the smaller ’56 Load O Matic distributor.
	Ford ECG 9424D Ford brought out this manifold as a factory option for 1957 “E Code” 312s. This picture clearly illustrates the path that the upper runners must follow between the down passages of the lower manifold plane. This aspect of the design is pertains to 2x4 and 3x2 setups and is one reason why single quad manifolds usually offer the best flow and power potential for street Y blocks. Note that the primary and secondary bores are arranged in such a way as to allow carb mounting either in a fore and aft or sideways carb mounting. Note increased clearance between distributor and rear carb, compared to the previous manifold. If you intend to purchase an ECG 9424D manifold, always check the underside of the manifold for heliarc repairs to the exhaust crossover heat passage. The most common reason for these kinds of repairs are cracks formed by trying to install the manifold over the standard valley cover pan, which is too high to be used with the ford dual quad manifold. A special valley cover pan was used by Ford with the “E Code” setup, so make sure you use one when installing this manifold on a Y Block.
	Edelbrock FM257 This big port manifold was intended for use with the 57 – up big port heads. It is probably the best flowing dual plane multiple carburetor manifold. Note how both carburetors are centered over the runners. This close spacing requires that 4150 and 4160 4v Holley carburetors must be mounted sideways, and actuated with a suitable linkage. The unique design of the passages in Y Block dual quad manifolds allows the primaries of 4v carbs to supply both manifold planes whether the carburetors are mounted parallel or perpendicular to the Y Block centerline.
	Edelbrock FM255 This manifold was intended for use on 55 and 56 Ford and Mercury Y Blocks, and its ports are sized for use on these smaller port (compared to the 57 – up ports) heads. Note how the rear carburetor overhangs the rear port runners.
	Edelbrock M254 This manifold was intended for the 1954 Mercury 256, which had smaller ports than the 55 and 56 Y blocks.
	Edelbrock FM573 This big port manifold matches the ports of 57 – up big port heads. It may be the best flowing 3x2 manifold.
	Edelbrock FM553 This manifold is the predecessor of the FM 257, and is appropriate for the smaller ports of stock 1955 and 1956 Y Block heads.
	Fenton DM424 I have no information regarding this manifold I believe this manifold is meant for small port heads.
	Fenton DM425 I have no information regarding this manifold. The owner has slotted the inner mounting holes to work with studs. I believe this manifold is meant for large port heads.
	Edmunds 3x2 Edmunds was a quality manufacturer of speed equipment from the flathead V8 days, along with Edelbrock and Navarro.
	Tawco 3x2 This manifold is occasionally seen for sale on Ebay. It is made in Australia for marine use. Note that it is a single plane manifold, a design probably selected for its low profile, useful in inboard boat installations. Using this manifold on the street would require fabrication of a water manifold for coolant.
	Edelbrock FM657 6x2 setups were used on marine engines and at the drags. The carb pads often have 0* angle, which means that 6* tilt blocks must be used for the street. Being an open manifold, low speed operation and fuel distribution between cylinders 1 & 2 is a problem. Gord MacMillan’s Y Block Magazine article may be a good place to start when setting one of these up.
	Weiand Dragstar Weiand is also a maker that dates from the flathead days. This is their 6x2 manifold for the Y Block.
	Offenhauser 3947 An Offenhauser version of the 6x2 setup. Offenhauser also makes the 6* tilt blocks needed for street use.
	Interceptor This marine manifold used Carter YH sidedraft carburetors to keep the installed height to a minimum. Some installations used only one carburetor. YH sidedrafts were also used on turbocharged Corvairs, 215 F85 Oldsmobiles, Corvette “Blue Flame” 6s, and Nash Le Mans 6s. Exhaust heat is passed under the cross runner of this unit.
	Interceptor on Thunderbird This beautiful Interceptor intake installation on a Thunderbird was accomplished by Gary Hartzell of LA Mesa, California. In Gary’s own words: “Wanted to do something out of the ordinary. Went to the Goodguys show at Del Mar last weekend (first show) and stumped a lot of Ford know-it-alls!!!!! One guy asked if I had to do anything special to make it run right and I told him I had to fill the radiator with salt water!! I had to fab my own necks to the radiator, but the installation wasn't too difficult at all and the results were well worth it.”
	Modified Interceptor This manifold has been modified to accept what I believe to be Del Orto carburetors, which are similar to Weber IDA carbs. Both offer a tremendous amount of tuning flexibility, and such a setup would look very nice on top of a Y. I include this picture to give an example of other possibilities the Interceptor manifold could support.
	Hilborn Fuel Injection These rare Hilborn Y Block units would not be suitable for the street, but would be hard to beat for pure top end power. Supposedly, less than 200 were made and when a unit is sold, it is usually for thousands of dollars.
	Algon Fuel Injection Algon and Enderle were early competitors of Hilborn, who pioneered constant flow fuel injection systems. This is an Algon version.
	Custom Tunnel Ram The following two pictures were sent to me by Ted Eaton, of Lorena, TX. Ted’s description of the manifold is as follows: “It is a short runner design with a large plenum volume, built by Lonnie Putnam.”
	Custom Tunnel Ram These four pictures were also sent to me by Ted Eaton of Lorena, TX. Here is Ted’s description of this manifold: This one is a long runner design coupled with a smaller plenum.  Designed by Don Chandler and fabbed up by Lonnie Putnam. This one is currently on the roadster running consistently in the 9.60's at 135 mph in the quarter. Great low end torque and top end horsepower
	Cragar + GMC 4-71 This blower manifold mounts a GMS 4-71 blower for stree and strip use. The manifold has been adapted for mounting the 4-71 with an aluminum plate. The pop-off valve is clearly visible in the 2^nd and 3^rd pictures. This valve relieves manifold pressure in case of a backfire, which would otherwise blow the supercharger off of the manifold.

---

back to HOME

back to Y BLOCK

This page last modified 18 October 2009