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