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The Ford Flathead

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Ford Flathead Engine

Project: Flat-Head

Identifying Our Engine, And A Little History


This is our Ford Flathead, just as it looked right after we removed it from the '33. While not exactly a diamond in the rough, it is a sound and complete example of what a Flathead Engine is and how they usually look when you find one.

To start out with, we acquired our Flathead Engine when we decided to restore our 1933 Ford Tudor Sedan. The engine wasn't to be reused in the restoration, instead it was replaced by the modern 4.6L Modular Engine Ford now produces in many of it's new cars. These Engines were first put into production in 1994, and at first were anything but powerful. Truth is the 5.0L that they were replacing had more horsepower then the new 4.6L Ford was releasing, and you can guess the feeling fellow Ford lovers had. Why would anyone want a new engine that produces less horse power then the current (5.0L) model? Especially when they were releasing this engine in there sports car line, the Ford Mustang. Eventually Ford began increasing the output of there new engines, and it wasn't too long before the little 4.6L was making some good horsepower. I go over this because the 1933 engine was very similar, this model year was also the first release of Fords new engine, the V-8 Flat-Head. It, just like the 4.6L, had many teething problems that were eventually worked out and allowed the V-8 Flat-Head to go on and become one of the most famous little engines Ford ever built. This new then engine, was the class of the Field. With more torque and horsepower then anything else on the market, that is anything the average man could afford!. This was made ever so popular by John Dillinger, he bought a 1933 Tudor sedan as his get-a-way car and was able to out-run all the cops. He even sent Ford a letter thanking him for producing such a nice and fast car. While Mr. Dillinger was eventually cough, he helped make the point about V-8 power and the two became famous.


The Flathead was produced all the way up until the 1954 model year. Then Ford in a race with Chevrolet, Dodge and other automobile manufacturers, started producing the Ford "Y" Block, Over-Head Valve Engines. In it's 21 year run, it was constantly fine tuned till the Flathead became darn near bullet proof as it neared it's final years of production. Even today, the Flathead is considered to be "The Engine" by many true Hot Rodders, for anything V-8 powered, especially for the early Ford cars and trucks.

Project COBRA'33 was not designed to use such an engine, this car was to be the pinnacle of Old meets New. In so, I wanted to merge the classic old lines of one of Americas best looking sedans with the raw power and convenience that all of today has to offer. The style of the thirties is long gone, but if it were around today, this is what they might be offering to the public. Who knows, there is a very strong segment of retro styling going on now, the old Camaro, Mustang and Challenger are all making a comeback, so who is to say the next HOT old ideal might be to re-live the thirties?? There is definitely a very large and effluent population segment that would surely like to re-live their past with just such a car or truck!! Project COBRA'33 has the latest of suspension systems, with a highly appointed Independent Front Suspension by Heidt. Along with a sophisticated 4-bar setup in the rear with Coil/Over Shocks and a Anti-Sway Bar. This type suspension allows comfortable cruising and aggressive cornering, all in one package.


Project: Flat-Head is first and foremost just an exercise to explore the limits and limitations of modernizing the Flat-Head Engine. From the very start, I intend to, with as much realization as possible, change our Flat-Head Engine into a Modern, Twin Turbo-Charged, Electronic Fuel Injected representation of what someone might or could do. This engine, although real, is not going to be a working engine when it is finished. Instead, this Flat-Head Engine will become a conversation piece, a Table, and hopefully a work of Modern Automotive Art. Yes I will be using all real parts, our Flat-Head is real, the Turbo-Chargers will be new, real and functional, the Inter-Coolers will also be new, real and functional, as will everything else, but the final product will not be a running engine, instead it will be a representation of what someone could do based on what someone else has done.

I'm very excited about Project:Flathead, this is something new for me, and I'm hoping others like your self's will like it as well.

The following is another article we printed from the Mega Squirt web site. This and many other useful topics are available at

Intelligent Engine Modifications

With so much misinformation and BS out there in the performance aftermarket world, we have decided to offer the reader some real tips based on 20 years of performance engine building and turbocharging experience.

Street or Race?

This is probably the biggest question related to successful mods and the most often ignored. Many people just don't understand why you can't drive a race spec engine on the street. Let's examine the differences in the 2 different worlds:


A good street engine should have a smooth idle, have lots of low end torque, a wide power-band, long life and good fuel economy. To get these characteristics, most street engines have relatively moderate camshaft timing, small turbos, small diameter intake ports with long runners and usually cast pistons. They are designed to run on gasoline with an octane rating of 87 to 92 RON in most cases and usually produce less than 100 hp/liter in naturally aspirated form and 120 hp/liter in turbocharged form


Ideally, a good race engine should have all of the same characteristics that the street engine has above but since high power output is one of the primary concerns, many compromises in those other desirable traits must be made to achieve this power level. To achieve higher power, ports are opened up for increased flow at high rpm and camshaft timing and lifts are increased, both of which kill off low rpm torque, power, fuel economy and that smooth idle.

The rpm capabilities are upped to permit higher airflow rates. This is usually done by changing to stronger parts such as connecting rods, pistons, crankshafts and valve springs. If the engine is turbocharged, a larger turbo and inter-cooler along with forged pistons and stronger rods are fitted to handle the loads. Raising the red-line will not make any more power in most cases unless the engine components are modified to efficiently pass that increased airflow.

On naturally aspirated engines, the compression ratio is often raised substantially to boost torque and power. This is possible when using high octane race fuel. On turbo engines, the compression ratio may either be raised or lowered depending upon fuel octane allowed, maximum boost pressure and possible fuel limits for the race.

As you can see, the two engines vary considerably in requirements and execution. The problem comes in when someone wishes to increase the power output of a street driven engine beyond reasonable limits while expecting no major degradation in "street-able" qualities.

Naturally Aspirated Engines for the Street

On most engines for street use, there are only a few ways to substantially increase airflow and thus power.

Porting the head will improve airflow if done correctly. If the ports and runners are enlarged greatly, low speed torque will suffer considerably.

Higher duration and lift cams are the main modification for increasing power. The more duration and valve overlap a cam has generally, the worse the low end torque, fuel economy and idle will be. Of course, top end power should be better. On most 4 cylinder engines, going with more than 285 degrees of duration at 0 lift will result in truly gutless bottom end power. With too much cam, the effective power-band becomes so narrow that the car is just plain miserable to drive in traffic. Most street engines spend the majority of their time in the 2000-4500 rpm range. Engines which are heavily cammed may not begin to produce substantial gains until above 4500 rpm and you are paying for this 95% of the time while being able to enjoy that top end only 5% of the time. We see more problems and complaints with people fitting race type cams in street type engines. It makes the EFI hard to tune and the car annoying to drive in many cases. Don't over cam!

Increasing the compression ratio is another way to increase power. It also increases fuel mileage. Unfortunately, the pump fuel available in most areas limits the compression ratio usable on the street to under 10.5 to 1 on most engines. The difference in power is minimal going from say 9 to 10.5 to 1 and it is a lot of work to shave the head or install new pistons. Again, if you get stupid and try to run an 12 to 1 CR on 92 octane fuel, you will suffer with lots of pinging and eventual failure. Many high compression street engines must have their timing severely retarded to avoid detonation which reduces the power right back to stock levels. Don't raise the compression ratio too high!

Raising the red-line to achieve higher airflow through the engine is another way of increasing power. To do this effectively, you will likely need to install a hotter cam with stiffer valve springs, port the head and possibly install stronger bottom end parts like connecting rods. The factory red-line is there for a reason. If you exceed it repeatedly by a large margin, you may eventually have a catastrophic failure.

Installing a header and free flowing exhaust along with a cold air induction system may free up a few more hp on certain engines. Don't expect gains of over 10% with these mods on most engines.

Nitrous oxide injection is used quite extensively in drag racing for a substantial power gain. When adding large amounts of nitrous, engine components may have to be upgraded to withstand the higher pressures involved. This is not usually a great mod for street use as everything must be just right as far as fuel and nitrous flow goes and of course the major disadvantage is that the tank runs dry after only a few minutes of use and must be refilled.


On street driven Atmospheric engines, there are minimal gains to be had on most small engines without sacrificing a lot of drive-ability. If you need more power, you need a larger engine usually. Expecting your 18 second car to do 13 seconds while retaining good idle and fuel economy when modified is unrealistic most of the time.

Turbocharged Engines for the Street

Turbos are a different ball of wax but many of the same mistakes are made when modifying them. Most of the same power increasing methods from above can also be applied to turbo engines. Because turbo engines usually have lower compression ratios than Atmospheric engines, they do not take kindly to hot cams on the street. The gain in top end will almost always be offset by a huge loss in the lower power-band and more turbo lag. Stock cams are the way to go on most turbo street engines. Don't waste your money on so called "turbo cams" for 4 and 6 cylinder engines. These may boost economy slightly but they almost always lose power. Most of these were designed by guesswork rather than by actual turbo experience. 4 Valve engines in general when turbocharged do not need hotter cams for the street.

Porting a turbo head will make the same type of gains as on an Atmospheric head despite what some people say. You can make the same power with less boost or more power with the same boost.

To obtain higher than stock outputs, the compression ratio should be LOWERED on a street turbo. This will permit higher boost with optimized timing on low octane fuel. Forged pistons are an excellent idea on turbos as they have 2-3 times the strength and heat dissipation of cast pistons. Forged connecting rods, colder spark plugs and stronger head gaskets are also recommended.

Stock turbos are usually sized for mid range torque and are undersized even for stock top end power. Compressor and turbine size upgrades are needed to realize substantial power gains. Going too large on turbos will lead to poor low end response. Turbos need to be properly matched for the application and primary intended usage. A couple of rules of thumb can be used if you have access to a compressor map. HP X 1.62 = airflow in CFM, HP divided by 8.07 = airflow in lbs./min. Avoid matching for efficiencies of under 65% at full power and operation near the surge line also.

Inter-cooling is extremely important. Stock inter-coolers with a few exceptions are total crap when used for performance application's offer low efficiencies and high pressure drop. Install a properly matched core from Spearco. The closer that your charge temperature is to the ambient temperature, the higher the HP potential will be.

Finally, boost pressures can be raised to increase engine airflow and power. This can only be done within the limitations of the fuel octane rating and ignition timing. Read the other tech articles relating to combustion and fuel for a better understanding. In any case, running 20 psi on the street is relatively meaningless. High boost pressure does not necessarily mean high HP. If you are running this kind of boost on the street, you probably have a host of mismatched or restrictive parts on your engine. With properly matched components and an efficient inter-cooler, one rarely needs to exceed 15 psi on the street. With these in place, you will be at the safe mechanical limits of most stock based engines and HP will be doubled or tripled over stock. Check out some of the cars on our project page prepared at Racetech if you don't believe this. Since engine life will plummet once you exceed this type of output, it is not a viable option for most people to be rebuilding an engine every 10,000 miles. You don't have a street-able engine in my opinion at this point.


Power may be increased substantially through turbocharging on the street but reliability will suffer unless it is applied correctly.

Turbo Race Engines

I will use a Toyota 2TC engine which I prepared for road racing use a few years ago as an example of what can be done with properly applied engine modifications and turbocharging. The stock engine starts out as a 1588cc, 2 valve per cylinder, push-rod, cross-flow Hemi. The stock hp is rated at 70 at 6000 rpm.

The block was bored out from 85mm to 88mm to fit Mahle VW forged pistons. This mod brings the displacement out to 1702cc and drops the compression ratio from 8.6 to 7.2 to 1. The rest of the block is totally stock as is the crankshaft.

The connecting rods were polished and shot-peen-ed. They were converted to a full floating pin arrangement to suit the new pistons and Ford SPS big block bolts were fitted to withstand the higher anticipated rpms.

The camshaft selected was the same cam we used on our race Atmospheric 2T engines with .430 valve lift/ 284/222 degrees duration at 0 and .050 lift respectively on 108 degree lobe centers. Valves were enlarged from 41 to 44.5mm on the intake via Ford 6 cylinder ones and from 36 to 38mm via Nissan 200SX ones. The head was extensively ported on the flow bench taking intake flow from 82 to 122 cfm and the exhaust from 66 to 86 cfm. Valve guides were shortened and bronze bushed for increased flow and heat dissipation. Exhaust seats were widened to .080 for better heat transfer. Norris triple valve springs and aluminum retainers were also used.

A stock oil pump was used and an HKS 1mm metal head gasket was fitted.

On the externals; A custom, equal length header was made using 1.625 inch ID thick walled tubing , a custom intake manifold was made fitted with a 70mm Mercedes throttle body and eight Bosch 490cc injectors. The turbo was a Garrett TO4 with H-3 compressor and a .58 turbine. This blew through a massive Spearco inter-cooler measuring 17 X 21 X 3 inches and 2.5 inch mandrel bent tubing. The exhaust was 3 inch mandrel bent tubing open. Fuel was M-85.

This engine produced 358hp at 7700 rpm at only 15 psi boost. The stock hp was quintupled! Engine life was approximately 6 hours at this power level and about 15 hours at 12 psi and 310hp. Eventually, the main bearing caps cracked from the power output but this was caught before major damage occurred. The effective power-band was 5000 up. Red-line was limited to 7700 rpm mainly for valve-train longevity although hp was still increasing at this point. This engine was used for road racing so the life expectancy had to be about a full season or 15 hours.


Turbocharged race engines can produce staggering hp numbers given strong enough parts however engine life goes down as power is increased. A narrow power-band may be acceptable on a race engine because close ratio gearboxes are usually fitted to minimize rpm drop between shifts.

There seems to be two types of people preparing turbo race engines for import drag racing. One school uses small, stock based turbos for quick spool up. These engines run super high boost but don't make any power. School two fits turbos which are way too large. These have poor turbo response and a super narrow power-band. They produce very high hp across only 1000 rpm on the top end and as a result are not very quick. Bigger turbos don't necessarily mean quicker times. Turbos must be properly matched on the compressor as well as the turbine end.

Some people really know what they are doing and some don't. 450 hp out of a 16 valve 1900cc Acura drag motor at 25 psi is just not impressive when years ago Jack Roush was producing in excess of 700 hp out of 8 valve 2.3 and 2.5 liter Ford Pinto engines for road racing events running from 2 to 24 hours.

Engine Displacement

For street use, you want as many cubic inches as you can get. Torque on the street is king. Always go for as many cubes as you can if you have a choice of engines.

Performance EFI Considerations

When increasing airflow through your engine for more power, you must also increase fuel flow to match. At some point, the stock injectors and possibly fuel pump will not supply enough fuel. Larger injectors will have to be fitted. As soon as you do this with the stock ECU, the engine will no longer run properly. You will have to either re-chip or install a different EFI system.

If your engine uses a vane type airflow meter, you are losing a substantial amount of power potential through its restriction. It is foolish to spend a lot of time and money improving engine airflow, then strangling it with a door type meter on the front. Engines fitted with this type of meter will usually gain at least 10% when changed to a large hot wire or speed/density type system. It is important to note that when the airflow flap bottoms out at high airflow rates, it is no longer capable of sending a proper signal to the ECU. The fuel mixture will no longer be correct.

Some companies offer rising rate fuel pressure regulators with their turbo kits to allow increased injector flow rate over stock pressure. Instead of adding 1 psi of fuel pressure per psi of boost as in a conventional FPR, they will ramp up at 2-5 psi per psi of boost. Some of these work OK at low boost but the fuel delivery curve is now in the hands of a mechanical device, not the ECU. This is crude at best. It takes 4 times the fuel pressure to double the fuel flow. If your stock fuel pressure is 45 psi, you will need 180 psi to double your fuel flow.

Two things happen here. First, many injectors become non-linear in fuel delivery above 60-70 psi differential or may not even open, leading to a possible lean out condition under boost. Secondly, the fuel pump is not designed to do this. It either can't produce the pressure or volume needed or will burn out quickly due to the massive increase in current draw. These are a bad idea at high boost pressures.


Use the right tool for the job. You don't normally use pliers to turn a screw in. It works, but not well. The same thing goes for performance EFI applications. Sure, you can trick an old L-Jetronic system with a resistor on the water temp input and get some more fuel out of the system but the method has serious limitations past a point and will not really supply the correct mixture across the operating range.

Courtesy of



This is our just sandblasted clean Flat-Head, ready for dis-assembly.

The first thing anyone has to do when working on a old Flat-Head engine, is to properly Identify it's year of manufacture. Our Project COBRA'33, was a 1933 Ford Tudor Sedan, but as we soon found out, that wasn't necessarily the same year as the engine. Flat-Heads had a rough start, the early engines had many problems. Casting techniques were poor at first and that lead to many early engine failures. The foundry had to place 54 individual sand blocks to cast one (1) engine block, and that left many doors open to potential problems. The early Flat-Heads had cooling issues, which resulted in block cracking and other problems. It would be very hard to find a pre-40's car or truck that still had the original engine, they just had to many problems and the owners swapped out the early Flat-Heads for the more powerful and more reliable later Flat-Head engines.

In-order to properly work on your Flat-Head engine, you must first and foremost know what year it is. This can be a rather confusing and frustrating task. The truth is, Ford didn't keep very good records of what they produced, and what they did track often makes little since.




Ford Flathead V-8


Engine Date Code

The (1932 - 1948) Ford V8 engine year of Canadian manufacture is identifiable by the code cast into the top of the bell housing, or on later engines (1949-1954) at the flange where the bell housing bolts on. Engine numbers that are preceded with the letter "C" are engines that were made in Canada. The Ford Motor Company of Canada produced engines used in all British Commonwealth countries except the British Isles. If you believe that there is an error in this table, please let me know so I can make the necessary corrections. Note that the "1954 " above is not a mistake. Ford V8 flat-heads were produced outside the USA well into 1954. If the engine is still in the vehicle, you will need to remove the transmission cover from the inside to see the code.

Canadian made 69A engine

Canadian made 1BA engine

Canadian made 8BA engine

The engine numbers are cast into the block as shown above and have been highlighted to make them more visible

The difference between a Ford and a Mercury engine.

The difference between the Ford and Mercury engines is not apparent from the outside. The important differences are INSIDE. The easiest way to determine if the engine you have is a Mercury is to look at the crankshaft front counterweight. The longer stroke Mercury has a dimple as you can see in the picture below. The shorter stroke Ford crankshaft does not have the dimple. The connecting rods are the same on both engines. The pistons on the Mercury are not as tall from the center line of the piston wrist pin to the top of the piston as the Ford pistons. Do not install Ford pistons in an engine with a Mercury crankshaft or vice versa!

Mercury crankshaft

Engine Serial Number

The engine serial number is not stamped anywhere on the engine. The engine serial number is stamped into the top of the flange of the transmission where it bolts to the bell housing. This was done to simplify registering the vehicle in jurisdictions where the engine number is recorded on the vehicle registration form. By stamping the serial number on the transmission, the owner did not have to change the registration when he replaced a worn out engine. So that means if the engine is of the correct year for the vehicle it is installed in, it is a numbers matching engine.

* The 8EQ Engine was used exclusively in F-7, F-8 trucks and Lincoln cars, and it was a monster! This engine can easily be identified by the location of the distributor, which is at the rear, on top of the block, next to the fuel pump and by the external water bypass tubes. The 8EQ engine displaced 337 Cubic Inches and developed 145 horsepower!

Engine Disclaimer!

The list above was complied from data found in many places. You may find variations of these numbers, totally different numbers or no numbers at all on your engine block. The numbers above are known for automotive applications. Ford built these engines for many other uses too. From powering standby generators in telephone exchanges and hospitals to generate electric power during commercial power outages; Lincoln arc welders; and inboard engine motorboats to name just three. If you come across an engine with codes different from the table above, it might well be a non-automotive application engine. And then again, maybe not. I'll leave it up to you to research it, and then when you have the answer, let me know too.


Flathead Specifications

221 & 239 Cubic Inch

Middle Years V8: 1938 to 1948

In 1938 Ford made new changes to the flathead V8, the most obvious change being the use of 24 studs per head instead of 21 as previously used. The engine underwent various other changes as years passed. In 1939 when the Mercury car line was introduced, the engine's cylinder bore was opened up for a larger displacement in the Mercury car. Changes to the distributor occurred in 1942 and again in 1946. The cooling fan was driven by its own v-belt beginning with 1942 models. The engine continued to be cast with the upper bell housing integral with the cylinder block assembly. In the post-war production both Ford and Mercury versions had the larger bore (3-3/16"). Water outlets were in the top center of each cylinder head for all 1938 to 48 motors.

Pictured at left is a 1946 engine (59A style)


(Cubic Inches)
Bore & Stroke

Maximum Brake HPCompressionHead StudsNotes
1938 Ford2213.0625 x 3.750856.20:1241,4
1939 Ford2213.0625 x 3.750856.20:1241,4
1939 Mercury2393.1875 x 3.750956.30:1241,4
1940 Ford2213.0625 x 3.750856.20:1241,4
1940 Mercury2393.1875 x 3.750956.30:1241,4
1941 Ford2213.0625 x 3.750906.20:1241,4
1941 Mercury2393.1875 x 3.7501006.60:1241,4
1942 Ford2213.0625 x 3.750906.20:1242,4,6
1942 Mercury2393.1875 x 3.7501006.60:1242,4,6
1946 Ford/Mercury2393.1875 x 3.7501006.75:1243,5,6
1947 Ford/Mercury2393.1875 x 3.7501006.75:1243,5,6
1948 Ford/Mercury2393.1875 x 3.7501006.75:1243,5,6


1) Used the "Eggshell" or "Diver's Helmet" style pre-war distributor (1932 thru 1941)

2) Used the "Crab" or "Pancake" style distributor (1942 thru 1945 engines).

3) Used the postwar style (1946 thru 1948) round distributor (similar to the crab style) with two bundled wire harnesses off the cap.

4) Prewar "81A" and wartime "41A" style blocks.

5) Postwar "59A" style blocks. These had the "59" cast into the top of the bell housing. Note that some of the 59A style blocks were also sold as replacement engines for pre-war 221 cubic inch cars and had the 3.0625" bore.

6) Had the two fan belt system (beginning with 1942 models) to drive the accessories. One belt operated the water pumps and generator. The other belt operated the cooling fan assembly.

General Information

The integral cast-in bell housing continued all the way through 1948 (except for the Ford trucks, which received in 1948 the newer '49-53 style engine with separate bell housing). All engines during this period had front, block-mounted water pumps (with wide belt pulleys), and twenty-four stud heads with center-located water hose outlets. Original cylinder heads for 1938 to 1942 were generally marked with "81A" for Ford or Mercury engines thru 1941; "81T" for truck engines from 1938 to 1942; "41T" heads were sold for 85/90hp trucks built from 1938 to 1942; "99T" for 100hp Ford Truck and Mercury in 1939 to 1941; and "29A" for Mercury in 1942. Heads marked "59-A" or "59AB" were used on all 90/100 hp (Ford & Mercury) engines from 1946 through 1948. The 59AB heads were sometimes used on earlier blocks in replacement rebuilds. You can find the Ford part numbers (basic 6049 and 6050 number with prefixes and suffixes) in the face of the heads and sometimes on the side edge of the head next to the intake manifold.

The postwar cylinder blocks were also marked "59" (or "59A" or "59L" or "59X" or "59Y" or "59Z") with raised letters cast into the top of the bell housing part of the block. The Canadian version had a "C59" cast into the same area. Another block assembly (the "41A" style) was used to replace the "81A" style cylinder blocks, which were all the 85/90hp engines with 3.0625" bore. The 1938 to 1940 blocks had four small "freeze plugs" (2 each side) in the oil pan mounting surface. The 1941 (except for a short carryover) and later blocks did not have the freeze plugs. These can be noted from outside an assembled engine by the slight "bumps" in the side of the block casting, right at the oil pan mounting surface. In mid 1938 Ford modified the engine for larger diameter main bearings. For complete crankshaft bearing specs CLICK HERE. The original engines from mid 1941 to final 1942 production (when WWII ended auto production) had a raised intake manifold deck surface. Prior to these engines, the entire manifold deck surface was machined flat, right out to the edge of the cylinder deck. The postwar engines seem to have returned to the practice of machining the intake deck all flat again. The foundry would also place what were probably "lot" or "production" numbers in the castings on all blocks. These were usually a small group of letters and numbers cast on the top of the bell housing....right next to the vertical surface of the back of the block. Unfortunately, any records of these numbers are long gone and they provide no clues as to the particulars of any engines.

Water jacket holes in the top of the cylinder area of the block will tell you what years the block may be:

1938 Blocks: Large triangular shaped holes between the center cylinder bores

1939-42 Blocks: Three openings between the center cylinder bores: top one is triangular;

center and bottom holes are trapazoidal (or keystone) shaped.

1945-48 Blocks: The three center openings: top one is triangular;

center and bottom holes are large round holes.

All 24 stud engines using cast iron heads were equipped with dome-top pistons (in either aluminum or steel). Engines built through 1939 had a pressed-on timing gear on the camshaft. Beginning in 1940 this gear was bolted on to the camshaft. All engines up through 1948 had "mushroom" style valve stem ends and split valve guides. Some engines (including 59A style) had removable hardened valve seat inserts. It's not uncommon for an early (pre 1946) engine to have the valve seats installed by an engine rebuilder at some point in its life.

As for original paint colors, the Ford and Mercury engines through 1940 were a dark green. Ford cars continued the color until 1942. Mercury engine had a dark blue color from 1941 thru 1948. Postwar Ford engines were dark blue thru 1948. Ford truck engines were generally the same as Ford cars during the years of this group.

Courtesy of Vanpelt Sales

What have we learned ??

While the engine casting code was really of no use, I was UN-able to match-up any of the letters or numbers with known codes, we still were able to narrow in on just what year our Flat-Head engine is. We know it has 59 A-B heads. which means it's at least a 1946-1949 casting. We also know that our engine block has the three center openings of a triangular top with two (2) round center and bottom openings, this places the engine in the 1945-1948 range. So right now it can be a 1946-'47 or '48. Our engine has 239ci of displacement and produced 100HP. The "J 57 1" engine code scribed onto our belhousing has not helped. I've looked everywhere and have not found on site that refeers to this engine code. While it would be nice to pin-point the exact year our engine was produced, it isn't really necessary, we have enough data that we can safely order replacement parts for our engine.

Project:Flat-Head is going to be a great little exercise, I'm really looking forward to it, and I hope you are as well. I didn't know much about the Flat-Head engines when I started this project, but now I learn something new almost daily. I can see the attraction many fellow hot rodders have for the Flat-Head, It's simple, reliable when working correctly and best of all it's history. This little engine changed the lives of countless people, no longer where they restricted to the small 4-cylinder engines or worst yet, the horse and buggy. Now Ford has built a engine for the masses, with power only seen by the rich, and with a price tag the average family could afford. Not only did this engine save Ford, it changed the world!

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