Hot Rods Flathead Durability

***le maybe a little misleading but here goes.
My 27 t coupe build Im considering a V8 flathead.
What I want is extreme durability as opposed to flashy parts or high performance. I dont have any expereince with them,Ive always ran sm block Ford, big Mopar and LS.
Right now its ford or the flathead.
My thoughts are last model year flathead with t5 and 3.73 gears.
Reason for durability is at times its not unusal for me to do a 18 hr drive ,1 way ,in 1 day.
Do not plan on ac as windows roll down and heat doesnt bother me.
Other than radiator and keeping them cool is all I know, Will build it myself so not afraid to put good parts in it.[found pay once and its over]
Thoughts appreciated.

 

Don’t go crazy on bore, compression, or overcarburetion. Get a nice distributor (I like points). Doublecheck piston to head clearance. Balance the ***embly. Spend extra time sealing up the leaky spots (I’ve never got a new fangled lip seal to work right on the crank, just use a rope seal). Good luck.

 

A well built flathead will handle long road trips as well as any other engine will as far as reliability engine wise. The issue with the older engines like Flatheads or older straight sixes is that they normally go less total miles before they show wear and need to be freshened up. I grew up in the time frame when if you drove your one owner Ford Flathead or other pre 1955 Car or truck 100K without pulling the head or without an overhaul and lived in a small town there was a good chance of you getting your photo in the local weekly paper with your car saying that you had gone 100K without engine work and it still ran good. That probably meant you were like my dad and faithfully changed oil ever 1000 miles.
To keep a flathead Ford, Mopar or any older engine working right mans that you WILL SERCVICE IT at the miles or time period it wants to be serviced at. No waiting until you hit 3 or 6 K and if you only run it around town for short trips and it never gets fully warmed up on road trips that means that you go on months rather than miles far as oil changes go.

 

I’m no expert, but keep it stk as much as possible like you stated to avoid extra costs. Get the original cam reground. Same with crank. I got Hi-lift Johnson lifters out of MI to avoid Chinesium issues. Use a Holley 94 and (Less expensive than Stromberg) and avoid the Ford-o-Matic? carb from the last version of flatheads.
I got a late 80s World Cl*** T5 that came out of a Mustang. Shifter location is perfect for my build, but most go with a GM T5 because of the different (shorter) shifter location. I rebuilt most of my T5. Had someone do the main shaft ***embly and final ***embly, but I did the countershaft myself. Had to get a longer Ford style input shaft to match the length of the old one (Ford truck trans). Got the adapter fir the T5 from Modern Driveline, but there are folks here that make them IIRC. Also had to have a custom sleeve machined and fitted to the front bearing retainer to match the Ford throw-out bearing ID. That was not cheap as no one sells them. Some parts are getting hard now to find for the T5, so keep that in mind.

 

If you want reliability, your plan to get good parts is smart. I would highly advise using pistons with a metric ring pack and hone them to the letter with the proper stones (as per manufacturer's instructions, and use a torque plate during honing process.

Cast iron rings are old tech. Ross pistons offers metric ring packs as an upcharge. Others manufactures (Wisco, etc.) may offer them as well.

As mentioned above, get the piston to head clearance correct and index the cam. While the heads are off, make a timing index so you can check timing periodically.

Keep the valve train as light as your wallet is comfortable with.

Use a steel strap for the center main to give the bottom end a little extra support.

Clean up any casting flash inside the motor to prevent it from breaking off later in life. Make sure you check the oil pump. New doesn't mean better, sadly.

Using a T-5 will help keep the RPM down on long drives on the highway.

 

I'll jump in here with a few additions and clarifications. First, I think when @Ziggster referred to a "Ford-o-Matic? carb" he was referring to the "Load-a-matic" distributor used on the 8BA series of engines. Properly set up, they are fine with a completely stock engine, but any modifications make them problematic. You will then go to a Mallory dual-point or a converted SBC distributor. Moly rings are superior to cast rings, so I would go with them, but for me, the extra expense of special pistons with metric rings isn't worth the extra expense involved for a street engine. I would also go with stock lifters, adjusted the old fashioned way (grinding the stems); there are always the slightly longer Chevrolet valves if things get too loose. I got a set of NOS 8BA lifters from Southside Obsolete just a few years ago. Then there are no worries with a lifter going out of adjustment. I had a bad experience with a new oil pump from Speedway Motors on my last build and ended up going with a tested original Ford pump with a new relief spring. I suggest that you do the same.

I agree with using some sort of overdrive. I hear that T-5's are great, but a stock overdrive unit is also a real slick deal if installed properly. Even if you're using a pre-49 flathead, a unit out of a '49- early '51 Mercury will bolt right up. I'll also second getting the piston/head clearance right (.045-.050") to obtain proper quench, as I think that it is the single most effective thing you can on a street flathead. And if you're looking for drivability over looks, avoid the multiple carbs in particular and older design carbs in general. Go with a more modern carb (either a 2-BBL or 4-BBL). I am partial to a small base 2G on a bored Merc manifold (the Canadian ones are aluminum), but I have several "square" pattern 4 barrel carbs and different manifolds I am going to check out "some day". If they don't work, there's always the old reliable 390 Holley to fall back to, but it will need an adapter.

 

The biggest nut to crack is finding a block that’s not.
Or one that isn’t rusted out.
Be patient and pay for the mag check, pressure check and ultrasonic test.

 

If they weren't reliable, would we still be building and running them 95 years later? Ford made 'em from '32 til '53, the French til '91 (?).
Here is a NOS Frenchie for sale on the Bay of 'Merica

 

Just because people keep using something doesn't automatically mean it's good. Just for example, the US sticks with imperial measurements out of stubbornness, not because the rest of the world is wrong.

 

Better oil and better filtration are a big part of why engines last longer today.

 

Paw Paw pounded on em regularly
Hauling logs, kids and critters
I’m saving up parts for a hopefull flatty build. 51 merc bell and ford OD trans. There’s a t-5 in the pile plus a couple toploader ODs
2 pot intake
Merc block and crank.
The cool part about the toploader is using a jeep shift tower. Puts the shifter in the cool spot

 

Thanks

 

Im not asking if they are reliable ,thats been proven. But doing a reliable rebuild with good parts and having knowledge is different.

 

I'm going to sell my NOS French block I bought when they first became available after I get through with some medical stuff, if that looks good to you. I'm in Tennessee. Block has been in the dry, untouched since I bought it.

 

My stock 8BA has sure been reliable. I have likely put 10k miles on it since August driving it daily and was even just up in Springfield, MO a couple weeks ago now.

 

But that is not on the engine, that is on the builder. I built mine to be fast and flashy, it has also proven to be reliable. Buy a cookbook and follow the recipe. That's how I did it.

 

Mostly correct, there are things in the world are still counted in imperial measures regardless of country. 1/2", 3/8th, and 1/4" Socket wrenches, extensions, swivels, adapters, etc. And real important stuff like airport runways and fairways, they prefer yards over meters, anyway all the European courses I have played do including the home of golf in St Andrews. So, if it is good enough for the Royal and Ancient Golf Club, it' good enough for me. Nothing quite as reliable as a good yardage book. Flatheads forever!

 

You know a friend of mine who worked for Chrysler (an old hot rodder) and I had a conversation as to why the older engines only went about 70 or 80K before needing work. Modern cars (this conversation was in the late 70's) easilly went over 100K, 150K was also common with good maintenance. His opinion was that we ran them way too rich back in the 50's and washed down the cylinder walls adding to wear. That's about the time Chrysler was into Lean Burn with 20:1 fuel air ratios. He was a really smart guy and had been in on the Chrysler Turbine project.

 

The French flatheads do at least get you 30-40 year newer parts and better casting techniques. $5700 sounds like a lot of money but you can sometimes go through several cores to get a good block. Good machine shops are fewer and further between. Probably not much more $ than you can build one for. Something to consider.

 

Since I was the original salesman for the French flatheads, I was “in on the ground floor”. The reason they are priced much higher than when they hit Texas(around Dec 1999) is “everyone wants to make money”——-they were a hot rodders dream, but at that time I was a family man with two growing sons bound for college and a wife that worked and we had a thing called a mortgage. Since I have enjoyed 60++++ years of buying,selling,trading all kinds of parts and pieces pertaining to Flatheads(over 50 engines) is how I “financed my love affair”of the Ford hot rods powered by Henry’s finest. I had built up a solid reputation as a small time “handler”,but catered mostly to the wants and needs of rodders in and around S .Texas.My heavy foot as a teenager led to my exclusive adoption of Muncie 4 speeds and 9 in Ford rear ends around1975. I will be the first to admit, I was a hot rod “flathead” *****—-meaning shove some good money my way and it can be yours.I have a GR8 s**** rook, but no parts or early Fords left.Moved from Texas(75 year resident) to right coast(DELAWARE) because Texas is too hot and the politics are “terrible”.FRENCH engines(250 complete long blocks with oil in them and dyno tested)came from Galveston to my hometown via 18 wheelers. I was friends with the “money” man and was given the job to “move them” and I did. B4 they were sold I was buying them for $1500 and selling them for $1800—making$600(for 2 engines) at swap meets in Texas. There was 400 bare blocks with main caps as 15 shipping containers made their way to my hometown. They were only available to me for a short period of time b4 they were sold to Halibrand and Motor CityFlathead. I did not have the money to invest at the time nor were they available for any length of time for me to make sure Henry ford parts would interchange,and only found out the interchange ability later in my “hot rod career” as a lover of Henry Ford cars and faster flatheads. True story—-FLATHEADS FOREVER!!!

 

Great read, John. Thanks for posting.

 

I added a few more pics/the engines I bought for $1500 were long blocks, full of oil,with a green dyno sheet on a skid that was complete. The 400 bare blocks and main caps showed up later(each one in a wooden crate)and I never even got a price on those because they sold quickly and left for Halibrand running out of an airport I believe in Kansas???? The homemade intakes were called Pacific Jackrabbit and were a joint effort of myself and a friend( deceased). FLATHEADS FOREVER!!!

 

As mentioned already using more modern air filters, oil and oil filters will noticeably improve durability. And while you're already into it rig up a real working PCV system too.

 

I owned a '49 Ford business coupe for about 10 years. I bought it from the niece of a retired Ford engineer that bought new. It was his daily driver. It had no back seat and only a platform. It was what we call a "broomstick" no options at all except for an aftermarket radio. It did have a heater though. I bought it for $150 and drove it every day for almost 10 years. It never let me down ever. All I did was normal maintenance. I ran it all over SoCal and didn't baby it. Flawless, I remember when I took it to Early Ford V8 tour. Someone came up, looked it over and said, "it's nice to see these old cars still being driven to meets like this once in a while! He got a real odd look on his face and walked away. When I did finally sell it much later, several people came to look at it. One couple came to look and had a very long and deep conversation well out of earshot. The car sat there idling all the while. As they were having their powwow, a cab pulled up and a guy got out, looked at the car and said he would pay my price and dismissed the cab. He paid in cash and I gav3 him the ***le. Off he drove, right past the deep debating couple. Much to their surprise. The husband came to me all excited and asked where the guy was going with the car. I replied that he bought it and drove it wherever he chose to. The guy got very mad and said, "But! We were discussing the purchase!". I said, "Well, while you were having an extended discussion, he decided and had cash in his hand!". Needless to say two people were delighted with the sale and two were VERY unhappy about it! But, I got my price and he got the car and both of us were happy.

 

Old engines are like marriages/relationships.
Sometimes your friends warn ya she’s crazy or temperamental buy you’re in love. So you ignore the “haters”
You either learn to live with it or …..well there’s some very well do***ented engine divorces posted here.

 

I have had my '51 club coupe since 1987. That's 39 years. I can honestly say it has let me down only once, and that one time was entirely my fault. About 10 years ago, I had installed a prototype of my 6 to 12 volt "Tach driver". (This was a device that allowed me to run any 12 volt tachometer on a 6 volt vehicle.) I had taken off to go the 20+ miles to town to buy a battery for my Corvette. On the way back, the car started running rough and finally flat-out quit. I called my buddy who had designed and built the device, and he came down to get me. After I explained what was wrong, he immediately disconnected the lead from the distributor to the device. The car started right up and I was able to drive it home, no problem. He subsequently found a problem in the design of the device and I have been running successfully ever since.

Other than that, it has performed flawlessly, including several long trips, one to Chicago and back.

 

Make sure to get as much **** out of the block as possible. My builder spent a LOT of time digging through the block with wire and tanking it to remove as much casting **** as possible. That stuff will plug up your cooling system and cause overheating. Mine doesn't overheat at all, and it's a pretty hot motor

 

Whenever I cleaned a Flathead Ford of “schegma”(anything that is not supposed to be there and often undescribable), I straightened out a metal coat hanger and made a small 90 degree turn down putting a sharp point on the end that I intended to drag thru the pan rail using the smaller of the two water pump holes pulling the pointed end thru with enuf downforce to loosen up the contents of the pan rail(factory often left a lot of “sand material” and over time it multiplies to even more “schegma”)/wash out with water;then find a discarded piece of plywood. Position the empty block on its nose, then vigorously slam the engine in2 the plywood(multiple times)—- intake side DOWN until all “schmegma” is virtually eliminated.Just because u paid good money to clean your block b4 machining,doesn’t mean the machine shop went the “extra mile” u are doing to make it very clean. You might be amazed as how much is left in the pan rail even after a machine shop “dunk”——FLATHEADS FOREVER FLATHEAD JOHN REALLY FROM TEXAS BUT NOW IN DELAWARE.

 

I have no dog in the hunt but I’m a believer in good manufacturers and the right parts like most have said. #1-I would build one using a modern ignition with a vacuum/centrifugal advance set to what the flathead likes. #2-I would use cast exhaust manifold that flow well and fit so there are no leaks. #3-(The most controversial) I would use a single 4 barrel preferably one of the early small base Carter WCFB’s or Rochester GC’s. They are direct bolt on with no adapter to available manifolds. They are estimated to be 325-375 cfm. 99% of them were on 8 or 8.5 to 1 compression engines so they are perfect for a flathead with added compression.
I have 2 on a 292 y-block and get 17 mpg on the road with. 3600# car. They have been trouble free for 9 years with no leaks and a stock 4 psi fuel pump…good luck.