My new military french flathead will be converted to a Hot Rod engine

you can still find new ones from time to time, but not the one with 4" crank . It's around 1500€.

They made the special pan just for the SUMB MARMON (4" crank)
The 3.9 l one (called "CARGO") got a regular design.
Miles from http://www.jackhammerspeedshop.com/ in UK had some for sale a few month ago.

 

I`ve seen three french flatheads with lifters turned into powder and chips.. Seems fragile as glass.. Hardening issues with a batch or a general problem..?

 

I might get you a "new" 4.2 liter with the 4" crank.
For 1500 Euros you can get the complete SUMB truck, not just its engine ...

 

Done some measurings, ended not so good that I first though.
The identificaton plate indicated that the bore and crank was stock, but it turned out to be .030 bore, std crank with some wear.
Found another identifiaction plate near intake

That might indicate that it have been serviced three times?

Tried to read the hour meter

But ended up with opening it up, and found that it did not work, due to leaking in water , I also think it measure total revs and nor hours, as it is driven by the oil pump shaft?

 

Was is delivered or did it surrender to you?

 

That's fucking priceless!!!!!!

 

Beware buying french transmissions along with the flatties....all the reverse gears are probably completely worn out. The forward gears should all be fine though.....

 

I want to order some parts for it, and a couple of question have come up:

- I want 59AB style heads, will they fit?

- What suggestions do you have on aluminum heads,I think I will go with the Navarro?

- Someone told me that the dome on the French flathead pistons are higher. I have measure the dome to about ¼” ? Will they fit the head?

- I need stud kit for them (Stock French uses bolts and one stud!) where can I get suitable kits? Price?

- Will stock french oil pump work?

- What oil pan should I use (stock one is of a uniq style, not useable)?

- On the stock main caps, the bolts are secured with a steel plate with tabs on, where can I get these?

- On the stock rods, the nut is secure bye asecond steel nut, where can I get theset
?
- Piston rings, Where can I get these, it,s a 3 ring compination stock French pistons 0.030 overbore, 1<SUP>st</SUP> & 2<SUP>nd</SUP> is 3/32, oilring is approx 0,196”?

- Gasket set, what to use?

- Regarding water pumps, which models will fit? I have a clearance issue with the front cross member and can only run a single belt from the crank, and it would need to be as close to the motor as possible, like 59AB, but I assume the fan belt will collide with the 8ba style distributor I like to use? But will the pump fit on block if I make an special pulley? or should I go with late truck pumps?

- Anyone using Vertex or Hunt "fake" magneto distributors?


- What suggestion do you have on a 2x2 intake. Is a Thicksthun working even if I go with stock cam?

- Is it possible to use stock French flywheel, with the 11" clutch?

- I would like to keep the stock pistons; the clearance is about .004” Is that too much? Its aluminium pistons.

/Ulf

 

Anyone?

 

I would give H&H FLatheads a call down in Socal. I think they may also be an Allience Vendor here on the HAMB. They could hook you up. If not point you in the right direction.

 

Yes, but I believe you have the same cooling passages to block off as on an 8BA

For a street-driven engine, buy the ones you like - there's not enough performance difference between them to even feel. Unless you're custom machining your chambers for an all-out race engine, use what you like. The Navarros are good pieces.

You should clay any head for both piston-to-head clearance and valve-to-head clearance. Shoot for about .050" over the pistons and about .100" over the valves (particularly the intake valve).

Any of the suppliers can provide a stud kit. Not up on prices. Bolts work just as well for a street-driven flatty.

I will assume that the French engines used the latest generation of the 8BA oil pump as the baseline. This is a quality pump. Look inside the inlet for helical cut gears - if they're there, run the pump as-is. You don't really need a high-volume pump and you certainly don't need a high-pressure pump.

I believe you have to use a 59A-style pan for the French engine.

Don't know, but you can drill the bolts for safety wire...

Again, don't know. But you can get aftermarket nuts from ARP that are stronger than stock.

Again, not sure what the exact sizes are for the French engine. You'll have to measure them and get with a ring supplier.

Any good quality gasket set. Fel-Pro or Best make good gaskets, but you may have to mix-n-match due to the combination of components a French engine has.

Sounds like the late truck pumps are what you need.

Can't help with this at all.

They're all pretty similar. A Super-style will give a little bit more power at the top end than a regular dual. The Thickstun and the Edmunds both allow a generator to be run in the stock location and on the street, will perform well enough that you may as well make things easier for yourself than try to find that last poofteenth of performance.

I don't know, but I would never run an 11" clutch on a street car. The 11" clutch was designed for trucks, is big, heavy, limits your bellhousing combos, and is stiff. A 10" will handle anything you can put out in a street-driven vehicle. The 9-1/4" from the 8BA is also more than adequate, having been used in the shoeboxes (some of the heavier cars with flatheads).

I assume you're talking about side clearance? That should be fine, I'd think. Depends on the material, but if they came out with that, they're probably just fine.

 

Try SF Flatheads.....they bought up all the French spares in the U.S.....on the motor I had, it had a 4" crank but the con rods and pistons were mongrels, perculiar to that motor and I bought a set of 7" rods from SF Flatheads and new slugs from Egge,, I think there is also an issue with the timing gear on the camshaft thrusting the opposite way to stock Ford Motors,the mains bearings were something like 1939 Ford if i remember correctly.In one of my rebuild books it mentions that on the french block you have to have made one extra long stud on each side.The 59a sump is the correct one but you have to weld the corner shut where the road draught system was.If fitting early heads, drill and tap and plug the forward holes on the decks.I fitted new speedway pumps as the french ones were siezed.The starter motor was a big 24volt thing I think, so I bought a mini starter designed specifically for the French Flathead, from Speedway.I cut the ugly boss off the rear of the block where the governor was mounted and ground it smooth and then modified the oil ways for a full(95%) flow oil system(very easy mod on these motors with a tapped take off already in place).The flywheel could have been used as an anchor for the QE2..that was going to be machined down a few pounds and redrilled to take a stock Ford clutch assembly.

There seems to be quite a bit of conflicting stories on parts for these motors, but that is what I found.

 

Comments from Mart are *like this*.

*Ernie speaks many wise words.*

Mart.

 

......cool......thanks for the thread.....very helpful.......

 

Why a stock cam????
A Schneider 270° works perfect with heads and intake.
Had a 4.2L French Flatead in a 26T Sedan. Quite fast!

 

I want to spend my money on the outer parts first, a complete cam setup will run about 800$, Il take that later if I need it

 

what's that issue in the camshaft gear on the french flathead?i remember that one hamber have problems to set up the french flathead .....him aligned the timing dots but the engine was very low in rpm...

 

How much will one of these run ya? And where can I get one? I've always wanted a flattie but been so afraid to get one because of the age and how big some people bore 'em.

 

I don't know what and how much of the US stuff you're going to use on your french flattie but here's what I did and hopefully I can give you some insight and perhaps save you from some grief (and $$).

I bought a french block and main caps and built it here in the states for my 40 coupe. I made blockoff plates for the rev limiter (whatever you call them) holes, installed a 4" crank, adj lifters, Elgin cam, and left it a stock bore for a 255 cube. So, all of the US hop-ups/parts/tricks will work quite well on these engines. This engine is hooked to an S10 5-speed. For all intents and purposes, top and front of the block is 8BA, bottom and back is 59AB. Therefore, you need to use the 59AB pan but you must weld up the breather hole and cut a relief in the block so the passage where oil would have flowed out of the block through that breather will run back into the pan. If you don't do this you'll have oil all over the place - ask me how i know!!

My block was factory relieved, I'm running a stock 8BA distributor w/Pertronix conversion, and 2 deuces. I run a "poor man's Thickstun setup" via an 8BA aftermarket intake and 4" risers. I use a 59AB fuel pump/oil fill stand so I have some breathing out back and a PCV valve through the front oil breather hole. The intake oil fill hole I plugged. As has been said before, a 10" clutch would be your best all around choice unless it's going into a real light roadster (or somthing similar) where a lightened 9" flywheel (the big ring cut off) would emulate the lightened alluminum flywheels. I have this in my 32 roadster with a 59AB flattie and 5-speed.

These blocks are super pieces, plenty of nickel in them, and they are a bit heavier than the US blocks. Less prone to cracking, if you get one they are usually pretty good. I've been running mine about 7 years now (got mine when Halibrand frist got them) and if you come from an area where good blocks are hard to find, you might save some money by getting one of these blocks. They do come up on eSlay from time to time and I've seen them go for $1500-2800, depending on completeness. There are some slight defferences in internal parts - rule of thumb is to use either the French or US rotating assemblies - the french cams are 8BA and they are good for grinding up to your specs - that's what I did and I bought a second I'm holding on to for a future build....

I've run this car at speed for hours at a time - great engine, ave's between 18-22 mpg, and no overheating probs.

I've attached some pan/block pics regarding that breather - hope this helps you somewhat ....

 

Thanks very much for the info, to you and all other that posted! I have been busy ordered parts, and havn,t been able to answer, I get there!

I will try to capture the whole build with my camera and put togheter what I found out.

 

Hopefully with all the info here, you will not have any bad surprises.
If you are unsure about anything, just ask.
Mart.

 

Just like Mart said, we're always here to help - all we all want to see is the "eye candy" - pics and progress of the build!

 

Swe:
I'm no engine builder but one thing I did do to the French block was open out the bowl area behind the valves.. I am told they act as a restriction to flow in the ports.
Do you intend to do that to yours, or will a cam and porting come later??

 

As Mart mentioned..the valve bowl area has a ridge cast around it.I ground and polished the ones in mine away....here is a before picture..

and here it is after an afternoons work....



http://www.flatheadv8.org/bishop/porting1.htm...this is the article i used for reference..


every little helps...good luck with the build.

 

Very nice work, I,m thinking of doing the same. For now I need to get everything cleaned up and do some strategy how to build it up.
I will get back to you all once I,m getting dirty again (First I need to make a rumble seat frame for the roadster so I can take it to the upholstery guy)

 

Finally got some parts! My coupe is used as a garbage shelf...


Now I can get started on the motor build. New parts are:

Navarro heads
Thickstun intake
Stromberg 97s
Hunt distrb.
Bearings
Gaskets
Used flywheel and oil pan
Truck water pumps

 

If you can possibly swing it, do the porting job and get a cam before you build it. The guy who had one on a dyno a year or so ago, couldn't get any power on the top end and I'm betting those ports and the cam were the problem. Years ago I ran a 3.375"X 4.125 on an Isky .400Jr, good cam.
Dave

 

a teaser...

 

Nice teaser pic, good thread too, I always wondered about the french flatties thanks!

 

I did a mock up and put it in the roadster to understand the issues with the pulley I want to run. This is because of that the crossmeber is mounted behind the axle and I now want to run 8ba styled distributor. It will be hard to get it working