Hi Guys, I just picked up an ECZ-9425-B (4bbl) intake manifold to replace the 2bbl on the stock 292 V8 in my 1961 F-100 4x4 4-speed.

I have a few questions, but first:

- I have no ideal what year/model vehicle it came from.
- I plan to MASSAGE this engine's heads by port matching, pocket polishing and surface plan/shaving, REPLACE the entire exhaust from a set of custom headers all the way back, REPLACE the entire intake with a "cleaned" 4bbl setup and then, finally, UPDATE the ignition once I do a little more homework in that area.
- I'm looking for parts that the factory would have used in that era (except the custom headers of course) UNLESS that is a poor choice due to the wonders of modern technology.

OK, on with the questions...

1. Will it work (fit, boltup, whatever) or do you guys see problems?
2. Is that the best ford part # that I can be using?
3. What carb should I bolt on to it? (a mechanical-secondary version that is under 500CFM, even after the Mods above, right?)

Any input is appreciated,

Thanks!

 

That manifold came out in 57 when Ford switched to the new distributor. It flows very good as is and with a bit of clean-up and head work it will run with the best. It was used with a few minor changes on the larger trucks thru 1964.

As far as carbs I would go with a 600-650 as you can then set the secondary stop as needed. The current style Holley, Autolite and Edelbrock (renamed Carter AFB) all work well.

Instead of wasting time on peanut valve 1960-64 heads look for various 1956-9 versions. I like the 56 ECZ-C for truck use as they pull good at the low end and you can still use regular gas most of the time. For max power the ECZ-G is the best but I doubt if the premium price on the market would make any difference in a non racing truck.

 

I have the ECZ-B manifold on my '61 unibody. I just recently performed a port and polish on it. I oval'd out the throttle bores, maintaining the dual plane design, matched the ovals to my 4 hole spacer, and smoothed out all the radiuses that I could reach (including the spacer where necessary). My heads have not been ported so I just polished the runners to avoid mismatching the manifold and heads. 10 hours straight of work with a dremel but it was worth it. It made a big difference. When I get used to this new power level I will have to find something else, relatively cheap, to squeeze out more! CD ignition or electric fans or something.

For headers try Red's Headers, Sanderson Headers , and Stan's Headers. Red's and Sanderson have long tube headers. Stan's has tri-y headers. Tri-y's are pricey but you get what you pay for. Stan's and Sanderson, I think, can do stainless if you want.

For ignition, Pertronix, and Crane have electronic conversions. MSD has a ready to run distributor. There was some problem a while back about the distributor gear being incorrect on the MSD but I think that has been straightened up. I believe that Mallory has a distributor for the Y-Block too. There are many companies that make ignition boxes and controls.

 

Great replies guys, thanks!

So the ECZ-9425-B intake manifold will work well with 1955-1957 ECZ-C heads to provide good "truck-ish" torque/power while still running on 87 pump gas, and bolting up to my '61 292 truck motor with stock internals?

If so, cool, but what 4-bbl Holley with mechanical secondaries, manual choke, running less than 600CFM with a "truck-ish" nature do you recommend? I’d like something of that era, but then again, 50 years have gone by; maybe there is something more modern. Lastly, it’s tuning needs to be simple with a "set and forget" design so I don’t need to grab a screwdriver and pop the hood daily in this ever-changing New England weather.

Thanks for the info Guys!

Bill

 

Supposedly, this motor makes 160HP stock. Should I expect around 200HP, more torque and better throttle response once the new heads/valvetrain, 4bbl carb/intake setup, full exhaust and ignition upgrades are added?

 

With the head & manifold upgrade you should expect close to 1956 performance minus the low lift 61 cam specs.

A modern ignition will improve starting and economy as well as not having to use jumper cables in the winter.


Where in NE are you? How about adding that to your profile so we all know.

Any carb from ~500 and up will work. The original 57 Holley was only a 390 and it ran out of pel too early IMO. I dont offer any particular suggestions since Im more into swap meet and junkyard finds than sending away to Summit for one. Lots of nice cores wasting away from the 60's era.

 

Carl,

I updated my profile by the way. Good call!

I *think* a 1956 292 with the ECZ-C heads and a 4bbl setup made 202HP. I'm guessing that with the milder, '61 cam profile, headers/exhaust and an ignition upgrade it can make the same, if not MORE, HP while still running on 87 pump gas, what do you think?

Back to the Carb choice... From what you're saying i should go with something that flows more than the 'ol 390CFM did back in the day. I'll hunt around EBay for a used, 500-650CFM Holley with manual choke and mechanical secondaries. Thanks!

 

If you use the C heads and give them a .050 cleanup cut you might hit close to 200 hp at some point on the curve coupled with a nice carb and exhaust.

Note that the hp and torque peak for the 56 are 400 rpm higher than the 61. Trucks like to make power at the low end where it counts.

The .060 over 292 in my F350 is built totally different than the 312 that is going in the modified/altered. One is to do serious work, the other to maybe get into the 10's.

 

Last January I purchased a 1956 Thunderbird with ECZ 9425-B intake manifold and a 600 CFM Holly carburetor that had several problems. The idle was rough and inconsistent, the car had an off idle hesitation, and a lean surge at cruise.

Additionally the ends of the manifold choke heat tube that runs through the exhaust passage were “plugged” with screws.

After the rough idle and off idle hesitation were addressed, I attacked the lean surge at cruise. The theory was that the engine was not flowing enough to properly “signal” the 600 CFM carburetor. The 292 CID at 2200 RPM and 75% volumetric efficiency will flow approximately 139 CFM, or 23% of the carburetor’s rated flow. So when cruising under light load, the flow was insufficient to draw the fuel required. The solution was to increase the primary jets size in a trial and test procedure. The end result was number 69 jets, 4 sizes larger that the original jets.

At this point the carburetor performance was smooth and consistent, but fuel efficiency was a disappointing 14.5 MPG and throttle responsiveness was not what I expected. Thinking through it again I realized that I was kidding myself by running more carburetor than the engine could possibly use. So, I build an Excel model to compute the flow required, based upon bore, stroke, maximum RPM, and volumetric efficiency. The 292 at 5000 RPM and 75% volumetric efficiency will flow 316 CFM. (If you would like a copy of this Excel model, email me and I will send it to you.)

A check of several Thunderbird parts catalogs showed a new Holley model 4160, rated at 465 CFM was available. I ordered the carburetor and a new manifold choke heat tube. When I removed the manifold I discovered that the old tube had been corroded away, only the ends remained.

Installation of the new carburetor brought the MPG up to 15 and the engine is more responsive. After learning all of this the hard (expensive) way, I purchased an original 370 CFM carburetor, which I just shipped off for remanufacture. I’ll let you know how it performs in 7 weeks when I get it back.

By the way, I did my researching in Dave Emanuel's "Super Tuning and Modifying Holley Carburetors" manual which I would recommend to anyone doing anything with a Holley.

Loon

 

Good info, be glad to hear from you in 7 weeks. One thing to consider tho is that this is a TRUCK forum and driving requirements are not always the same as a T Bird. Note that the thread originator has a 4 x4 with a truck style 4 spd. Not exactly a stoplight dragger.
Also I hope you are not running the 56 distributor with those carbs.

As far as that formula Ive had discussions with pro race builders over the years about that.
The concensus is that it is derived from theory and in practice it is off by 30-35% based upon dyno testing. I did a quick look for the formula they use but dont see it handy; I'll look later.
There is also some flow discrepancy about Holley specs.

I became a convert myself when I had a whole weekend to play with a dyno last year on a fresh 276 inch flathead with a hot street cam and serious flow work on the block. The best run was with a modified dual carb manifold and a pair of Holley 2300's totalling 600 cfm.
Was it streetable? No, as there was no way to control throttle response as in real world driving. Good race setup only.

Ive spent a fair amount of time this summer building up other drivable combinations and once drag race season winds down I'll have access to the dyno again.

Another thing pointed out to me was that the Y block as well as many other engines of the era have poor distributors, advance curves, and ignition levels. To that end I had my distributor modified to take the Mopar HEI module and recurved based upon the specs of the engine and what its intended use.
With an Edelbrock 573 intake and 3 highly tuned 2100 style carbs on my .060 over 292 Y I am extremely happy. Granted a Blue Thunder intake and a ~600 cfm carb would be better but I was more into the looks. My F350 can now better compete on the interstates which was the basic goal.

Over the winter a 312 will be built for an Altered class nostalgia T roadster drag car. That will bring around another series of dyno runs and the guys are real interested to see what an ancient design coupled with modern technology can perform.

And while Im on ignitions, it has also become obvious that technology has made gains in that area also. The pulse system used by Jacobs and others has shown huge improvements in not only economy but in its ability to handle higher fuel flow while increasing power. While appearing to be from the 60's the dragster will use as much modern help as it can get. SBC's beware!

 

Carl,

I wanted to share my experience with carburetion on a 292 Y block and only mentioned the fact that it was installed in a Thunderbird for reference. This 292 is the first Ford engine (let alone a Y block) I have owned and I have a lot to learn. The FTE site is the only site I have found that offers such incomparable discussion regarding Y blocks, so I beg you to indulge me even if the top on my Thunder-truck is removable.

When I got the engine it had a ’56 distributor that the dual vacuum diaphragm had been replaced with a single vacuum diaphragm, which basically provided no advance at all. I replaced that with a stock ‘57 distributor that I am currently running. And I just purchased a Mallory standard advance, dual point with the tachometer drive housing (some of the smaller trucks had mechanical factory tachometers). After I purchased the Mallory, a friend cautioned me that the original coil might not support the Mallory. I’ll let you know what I discover when I install it.

The Thunder-truck originally had a 312 installed and I located a correct casting number 312 with ECZ C heads. My engine man just completed rebuilding the engine and I am working hard to sort out the accessories before I do the engine swap.

Loon

 

Loon,

You sound like you know what you're doing, so I hope you don't mind some advice anyway.

Did your machinist 'zero-deck' the engine? Ford was doing quench designs back then and your engine, with the ECZ-C heads, will benefit from a 'zero-deck' and a head gasket about .040" thick. It will need less timing if the quench is optimized.

Are you using a stock cam? John Mummert has some custom grinds. And have you cleaned the intake manifold, especially the exhaust cross-over? That would help with fuel atomization, part-throttle operation, and economy.

And if Carl will forgive me for clarifying one of his comments, "There is also some flow discrepancy about Holley specs", a Holley 600 CFM carburetor will never flow 600 CFM; They're over-rated.

 

Paul,

Let me start with a correction to my first post, the original Holley model 4150 that I am having remanufactured is rated at 400 CFM, not 370 CFM as I first wrote.

My engine man runs a small (three man) shop that is very well equipped and came up squeaky clean with ASAE and BBB. As a teenager his first car was a ’56 Mercury with a 312. He told me we should ‘zero-deck’ the block, so we did. I had him install a new stock cam, hardened exhaust valve seats and machine both intake and exhaust valve seats concentric 3 angles. The rockers are the 1.54 aspect ratio version, so I expect the engine will flow well for street application.

I did have the “B” intake manifold thermal baked and steel shot abraded when I had it off the 292 to replace the choke heat tube. That is a new process since the last time I built an engine, and while I was skeptical before hand, I was impressed with the results.

I truly appreciate your clarification on the Holley flow ratings. Since I have a new 465 CFM and soon will have a remanufactured 400 CFM, I will do a series of performance and efficiency comparisons and let you know the results.

 

Thank you for the courteous response, you do indeed know what you're doing.

I'll be interested to hear how things come out. I, too, am in the build-up process of an overbored 292 with a -B intake and ECZ-B heads. I have a varietly of Holley carbs and the original Autolite carb so the information you learn will be immediately applicable to my 292.