Part 124: Testing & Tuning a Holley 4000 on the 1955 Ford Fairlane

The Summit 500 cfm carburetor has given wonderful performance on the Mummert intake!

What is a Matter with You?

Faithful followers of the blog already know that my 292 Ford Y Block has been fed by an ECZ 9425 B intake for many years. That intake has carried an Edelbrock 1404 500 cfm and a Holley 1850 600 cfm. I have been pretty happy with those two carbs, but a few years ago I made a tremendous upgrade with the Mummert dual plane intake manifold. Not long after that switch I replaced the Holley with a Summit four barrel 500 cfm - it does seem to be the easiest to tune. It certainly does look to be a great combination. So why am I removing the pair and installing a sub-par ECZ 9425 A intake manifold and matching Holley 4000 carburetor?

The Mummert intake manifold is a top performer and most will wonder why I removed it!

My 292 has run both a "B" intake and the small Holley 94 intake, but never an "A" manifold.

I have been out in the California sun, but I do not think I have lost my mind. Not entirely anyway. The idea of installing this 1956 cast iron four barrel intake and matching carburetor is just an indication that I like to tinker, test, and tune. My claim to fame with these carbs for anything notable would be that I rebuilt the Holley 4000s that were ran on the 1956 Fords in the movie Loving. That movie/documentary was filmed in Virginia, on location where the historical events took place. My friend Wayne Francis owned the cars and loaned them to the production company. In addition, I have rebuilt and/or modified quite a few of these quirky carbs over the years, including a 1956 ECZ model that was set up for a Paxton McCulloch blower.

The irony is that I have never run a Holley 4000 on any of my own vehicles. I figured now was the time. I had just completed the video that explained how to modify the Holley 4000 for the distributor vacuum signal to "speak nicely" with a unit that has both vacuum and mechanical advance. (Visit eatonbalancing.com to find out more - my friend Ted has a great list of articles!) Having a boatload of parts and a great core that I used for the video it was time to show how install, test, and tune a teapot for my personal car. After all, I do plan to run a 1957 2x4 setup when I finally get my 312 together.

Preparing the Manifold and Carburetor

It may sound simple, but there are a few tips and tricks I use for installing an intake manifold on a Y Block Ford V8. Always ensure your mouting surfaces are clean and straight. I make it a point to thoroughly remove all the old gasket material. This includes the thermostat housing.

The cast iron thermostat can withstand the abrasiveness of a powered wire brush cup.

Be wary of pits in any mounting surface - quality sealer will help fill microscopic voids.

The intake manifold needs to be as clean as possible before installation.

Beyond cleanliness and checking to ensure that all mounting surfaces are flush, I recommend quailty gaskets. Unless you run your Y Block in an extremely cold climate, it would be a good idea to block off the exhaust ports with thin steel shims or to use a Best Gasket version of the intake manifold gaskets that already have the metal shim integrated into the gasket. These include a small hole that limit the run of heat through the exhaust crossover of the intake. This keeps your paint from burning off the intake and helps your carburetor to run cooler. The improvement will really help your fuel delivery if you run gasoline that has ethanol in it.

Best Gasket makes the "best" gaskets for the Y Block Ford V8!

For gasket sealer, I use white lithium grease for the runners and hi-temp red Permatex silicone gasket maker for the coolant ports, exhaust ports, and the thermostat housing. Everyone has their preferred elixir I'm sure, but I use these products to make it easier for me to re-use the gaskets for the next time I swap intake manifolds. This has worked very well and I am now on my fourth use of these gaskets over the past 5 years. Another tip would be use a product called "sil-glyde" - NAPA and other brands have their own versions. I use the slippery sealer for radiator hoses, heater hoses, and the water pump by-pass hose. Not only does it help seal well (of course the clamps are a big help here) but the sil-glyde really helps to ease the removal of the rubber from the metal. As you are aware, there is a tendency for rubber to stick really well to cast iron, brass, aluminum, etc the longer it is clamped to a water neck or tube. Sil-glyde helps with this immensely. I really like using the product.

For the installation, I always install the thermostat and housing while the intake manifold is on the workbench. This really assists me to ensure that the housing seals to the intake manifold - very few things are as frustrated as popping the hood the morning after an intake manifold installation only to find that the thermostat housing is leaking! I do leave the by-pass hose clamped to the water pump by-pass tube. After coating the gaskets with white lithium grease and Permatex, I also coat the thermostat housing by-pass tybe with sil-glyde. For all practical purposes, I like to hold the intake over the valley pan with the gaskets in position on the heads, lower it towards the block at an angle and simply slide it forward into the by-pass hose while setting the manifold down on the gaskets. This really tends to work well.

Custom pieces from the hardware store made the linkage work just right.

Examine the pictures below:

The photos above show the intake manifold bolt bosses on a loose head on my work bench. The 2nd and 3rd photos show the push rod chambers, and if you look closely you can see the light shining through a threaded hole. Warning: be sure to use the appropriate length bolts at these four areas on your Y Block. (These are the front and rear on both sides.) If your bolt is too long you will scrape or even bind up a push rod.

Testing the Choke

Since I had replaced the original thermostatic choke with an electric version, I figured it would be wise to test the action of the choke while I had the carburetor on the workbench. After all, I had completely disassembled the Holley 4000 (including the choke), used a nice kit from Daytona Carburetor, and made the vacuum modification as well. I hooked up a 12 volt power box (this converts 110 volt AC to 12 volt DC) to the choke and it only 4 minutes for the choke to open fully.

The video below shows the process and a small adjustment that I had to make. I did have to flip the thermostatic spring around inside the choke cap. As shipped, the winding was actually closing the choke the hotter the spring became! This could have been corrected after installation and finding this out while running the engine, but discovering the technicality with a simple test on the workbench made for a trouble free session under the hood.

Dead in the Water!

Torquing everything together was pretty straightforward. Of course, I did have to work on some plumbing and linkage problems. However, this did not take long, and a quick trip to the hardware store to pick up some all-thread resolved the linkage issue easily.

Very quickly, this Holley 4000 carb and intake swap was taking place on the 292.

After double-checking the carburetor settings (idle mixture screws, choke cap, choke fast idle idle set screw, etc) I decided it was time to fill the fuel bowl and fire it off! The electric in-line fuel pump always makes it quite simple to bring fuel up to the carb with just a flip of the switch. In just a few seconds we were ready to go. I even checked on fuel pressure psi and ensured that the needle and seat were working well. No leaks, no problem, ready to fire.

I did not have to even pump the gas pedal - a simple turn of they key and the engine fired right off. Even the idle was pretty good. I let the engine warm up enough to allow the choke to fully open, turned off the ignition, and then started it all up again just to check a hot start. No trouble.

After I turned it off a second time, I turned the key again to check another hot start. The Y Block turned over well but did not fire. I pumped the gas and turned the key again - nothing. I tried cranking and pumping the accelerator pedal and trying to start it again - nothing. After walking around to the engine bay I confirmed I was getting fuel.

"Must be ignition," I muttered to myself. I looked around the coil and distributor for any wires that may had become disconnected or loose. During this process I felt the coil. It was overtly hot; like really hot. I removed it and put it on a worbench for a resistance test. Yep, 0.00 ohms primary reading - dead in the water. Only one side read true for the secondary, so this confirmed the trouble.

During the video, I take a shot or two at those that raise a ruckuss over the "towering inferno."

I ordered a new ACCEL coil (8140 - it has an internal resistor) and tested it as soon as it arrived. Ignition parts are always a little sketchy in my opinion. I am a firm believer in testing on the workbench as you can tell. These days, with so much being manufactured overseas or made to low-quality specifications you can never be too careful. I have run the previous coil for almost 15 years so I think I did get some good use out of it. The primary resistance on the new coil was 2.1 ohms and the secondary reistance was 9.82 ohms.

Testing the new coil on the workbench will save some frustration before installation.

After installing the new coil and reconnecting all the wiring, it was time to fire off the old Ford once again. The video shows the evidence - a quick turn of the key brought the 292 Y Block back to life. After letting the choke pull off and the engine come to operating temperature, I set about adjusting the idle mixture screws and the idle adjustment. I was already satisfied with the fast idle setting for the choke's mechanism. You can tell in the video above that things just ran extremely well straight off the bench with initial settings, but I still wanted to fine tune the carburetor. Things were so good with initial adjustments that even the exhaust from the tail pipes looked good. (or didn't, it was kind of hard to see anything)

Believe it or not, the choke was on and the engine warming up with no black smoke!

This go around I just tuned by ear, listening to the engine, guaging rpm, and letting the exhaust note tell me where I was at when making small incremental turns of the idle mixture screws. In the end, the idle screws needed to be turned out about another 1/2 turn or so to richen the mixture. I got the idle as smooth as possible, and like both the Holley and Summit carburetors, the engine still does best at 650 rpm or so. A few years back when I installed the Isky E4 camshaft the nature of the idle certainly changed for the 292. Of course, this is not necessarily a problem - I happen to like the exhaust note.

The modified 1956 Ford air cleaner and Holley 4000 look to be at home under the hood.

Over the next month or two I will include a report on how the "new" setup is responding and performing, especially as the weather begins to heat up out here in the high desert. On the horizon are a few more goodies for fans of the Y Block. I just received a 3x2 intake in the mail, and I now have three Holley 94's that are on the workbench just waiting to prepared for modification to work in harmony. It seems that I cannot just leave well enough alone, and the tinkering on this old Ford continues.

Easter Services

This past weekend around the world, followers of Jesus Christ celebrated his resurrection from the grave roughly 2000 years ago. Our church had a special presentation of the crucifixion and resurrection of the Lord Jesus, and we have uploaded the video to the YouTube channel of Lancaster Baptist Church. I hope you will take some to watch the service. On the video slider, the presentation begins at 17:14.

https://www.youtube.com/live/nKAffj-HsUM?feature=shared