Interesting bore dimensions

[51504bat]

My suggestion on heads is try to find a set of EAB heads. If not then use 8ba's with 8rt's being the last choice. The EAB heads have the highest compression ratio followed by the 8ba's with the 8rt's being the lowest. I've got EAB heads on the basically stock 8ba in my '39 p/u. It supposedly has a Merc cam and a Buba Chevy conversion distributor. More than enough power for my needs. YRMV

[GB SISSON]

Originally Posted by 51504bat

My suggestion on heads is try to find a set of EAB heads. If not then use 8ba's with 8rt's being the last choice. The EAB heads have the highest compression ratio followed by the 8ba's with the 8rt's being the lowest. I've got EAB heads on the basically stock 8ba in my '39 p/u. It supposedly has a Merc cam and a Buba Chevy conversion distributor. More than enough power for my needs. YRMV

I think I have some, I'll go look.

[Bored&Stroked]

I'm with Tubman - bore it 1/8" to 3 5/16" and you'll like the power from the additional cubic inches. Heck, throw the Merc crank in it (as you have to order pistons anyway, might as well run the 4" crank). You'll have a sweet running 276" flathead - a great combination!

[GB SISSON]

I found both EAC and EAB heads, but I thought I recall that merc heads made for less compression. ?? Sounds like EAB what I want.

[51504bat]

EAC heads with a 4" Merc crank will be fine. But Merc EAC heads on a Ford 3 3/4" crank means lower compression. If you've got a pair of EAB heads in good shape that would be the way to go. IMO

[flatford8]

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Gary,
That’s what I have in my ‘51 Tudor. 276 with milled EAB heads. Retirement starts tomorrow so I’ll finally have time to finish it……..Mark

[tubman]

I still believe that getting the quench and compression optimized is still one of the best things you can do on a flathead to increase both power and fuel economy. Getting to .045" to .050" over the piston crown is where you want to be. It's a simple matter to bolt the heads on with a set of used gaskets and measure the clearance over the piston with foil balls. The easiest thing to do is to figure out the smallest clearance over the piston and have the heads milled to bring it down to the .045"-.050" figure. Do not be surprised if each head needs to be milled a different amount. What I do is to have the heads milled to be .045"-.050" clearance on the largest existing clearance and then use a die grinder to bring the others into spec. I'm skating on thin ice here, because I have only done aluminum heads which are a lot easier to work than cast iron. In the end, I would think that a properly prepped set of 8RT heads would be superior to a set of "raw" EAB's, but, as I said, I have no real world experience with that particular exercise.

I have never had a problem with clearance over the valve heads with a stock (both Ford and Merc) cam. Also, by getting the quench correct, the maximum practical compression will follow. Sure, some major combustion chamber mods can be made to bring the compression a bit higher, but for a street engine, that's like chasing the rainbow.

[GB SISSON]

OK thanks much you guys and Mark!!!! I can't even imagine what that must feel like. Congratulations! I'm just gonna taper off as the years go by. Kinda nice telling the annoying customers and slow payers to take a hike. Here's some pics of this morning's haul. Will I need a truck oil pan? I have a pan with a big cleanout plate, and some cast iron bell housings. Most of my recent trucks have been '47 and earlier style engines, so will have to be reminded what this will require. The kid directing the 8ba back into that '51 F3 is 28 now and that was my first flathead 'hillside garage overhaul'.

[petehoovie]

Originally Posted by GB SISSON

OK thanks much you guys and Mark!!!! I can't even imagine what that must feel like. Congratulations! I'm just gonna taper off as the years go by. Kinda nice telling the annoying customers and slow payers to take a hike. Here's some pics of this morning's haul. Will I need a truck oil pan? I have a pan with a big cleanout plate, and some cast iron bell housings. Most of my recent trucks have been '47 and earlier style engines, so will have to be reminded what this will require. The kid directing the 8ba back into that '51 F3 is 28 now and that was my first flathead 'hillside garage overhaul'.

[38 coupe]

I'm also on the EAB head bandwagon. Do you have a used head gasket laying around? If yes, after you have the crank, rods, and pistons installed bolt each EAB head onto the engine with the used head gasket and measure clearances using the foil ball method described above on each piston. Don't be surprised if a head is warped and one end needs more surfacing than the other. Record what is needed and surface accordingly, you can use a dial indicator and magnetic base on the surfacing head so you adjust the ends of the head to remove what is needed. We did that on what turned out to be warped EAB heads for an 8BA (my dad's engine) and it worked really well.

Look through your used Ford camshafts for one in nice condition. Since you are looking to maximize low speed torque instead of mid range power the best cam for your engine is probably a stock 8BA cam. That has the shortest duration of any of the 49-53 camshafts and should build low rpm cylinder pressure best. Ignore suggestions to use an 8CM or EAB camshaft, they are better in the normal driving speeds that you don't get to on your island.

[GB SISSON]

I continue to generate more questions than answers and I have been taking notes on the thread about putting an 8ba into a '46 car. I found two of the truck oil pans, a couple different bells and plates, one water pump that looks like the correct truck pump and so on....I have quite a few crank pulleys but not exactly sure how to identify the right one if I have it. I'm sure I will run a gm one wire alternator and I found both types of slingshot hanging on a nail. How do I identify an 8ba camshaft? I have taken apart at least one merc engine in the past so that cam could be around mixing things up. I know there will be a gear on the snout. Oh, and Les, the machinest sounded like it's a nice job for him, being all clean and disassembled and in good shape. He likes the .125 over bore and said we can talk pistons when I drop it off next week. I also noted there are no cam bearings in it. He DID say he's really busy and it will be two months before he can get to it. That's ok, I don't drive the woodie in the winter, but the fourth of July parade has become a high point for my 5 grandkids so there is some urgency after the block comes home. Gonna be lots to do and don't forget the transmission needs some real attention or replace??? Never a moment's rest, just the way I like it! Thanks all for the help!

[38 coupe]

Trying to answer questions you mentioned above:

Use a wide belt crank pulley. The 8BA era ones are visually different from the 42-48 era pulleys. The later sheaves are closer together, the earlier sheaves are further apart. The front belt that runs the fan is in the same place on both engines, but the belt that runs the water pumps and generator is moved forward on the 8BA era so the belt leaves room for the distributor.

Use the starter plate that matches the bell housing. My memory is the stamped Mercury bell housing uses a starter plate that is flat behind the flywheel and the cast truck bell housing uses a starter plate with a recess towards the flywheel. The recess is to clear the aluminum seal thing (I don't remember the name of it, I just install them).

Truck water pumps have a lower ear than the Mercury water pumps. If the ear is down near the water inlet it is a truck pump, if the ear is up near the pulley it is a Mercury pump. You want truck pumps.

8BA camshaft will have the gear on the front to drive the distributor. I don't remember if there is any identification cast into it. The Mercury and later Ford camshafts will have something cast in them, 8CM, 1CM, EA, etc.

Post pictures of the stuff you are thinking of using and we can all help ID parts and assist with advice if anything looks like it is missing.

[GB SISSON]

Here's a start. First thing I noted on this crank pulley is the lack of a machined surface for the seal. Looking at my crank on the bench I see a woodruff key in that location, so I guess that takes a sleeve piece. I also have what I recall is an 8rt, mostly disassembled but still has the crank and cam in it. It has that pulley, but very bent and gives me an Idea how it's set up. I know I have 2 of these cast iron bell housing pieces, but a quick look yeilded one and two starter plates, not sure about that indent though. The 8rt engine should give me the aluminum rear seal holder and the crank snout piece. We have a houseful of guests so Ol Gramps will need some away time in the shop, which will allow me to get more pics of water pumps etc. This is my first time assembling a V8 from a mixed bag of 'found' parts so please excuse my lack of knowledge in this area. The others were complete engines that I put back together with the labeled parts that were removed, cleaned and painted. Looking through some Old pics I see this engine that came with a bunch of stuff frome East of the cascades. In a weak moment I sold it for 500 bucks to defray the cost of the trip and the missed two days of work. What a dunce....

[Ol' Ron]

I've been folling this thread and I think the real question iscost vs performance and econmy. Try this: Offy 3 5/16 Hyper utectic pistons and rings 600 bucks installed in most shops. This gives more cubs and a point in compression. Now for the trick stuff EAB cam and heads. The heads will work on a 59 block as well use gasket for the head. plug the thermostat bypass hole/ Use8ba distributor cover and loadanatic dist & carb. 12v alt and electric fan and fuel pump narrow bely passenget pump pulleys ETC. Finished product less than 3K Power and econmy and a 100,000 ride. Plan ahead!!!!!

[38 coupe]

The bell housing looks like a cast truck unit. The starter plate appears to be a flat Mercury unit, but I could be mistaken it is a bit hard to see in the picture. The crank pulley is a truck unit, and yes behind the pulley you need to use the spacer with the grooves for the rope seal. Either oil pan should work, I recommend taking the clean out plate and associated retaining parts off the pan and cleaning everything, then reassembly with your favorite sealing goo.


The engine in the front of your picture is a 53 truck version without engine mount ears on the water pumps. You want pumps like the engine in the background.

[petehoovie]

Originally Posted by GB SISSON

Here's a start. First thing I noted on this crank pulley is the lack of a machined surface for the seal. Looking at my crank on the bench I see a woodruff key in that location, so I guess that takes a sleeve piece. I also have what I recall is an 8rt, mostly disassembled but still has the crank and cam in it. It has that pulley, but very bent and gives me an Idea how it's set up. I know I have 2 of these cast iron bell housing pieces, but a quick look yeilded one and two starter plates, not sure about that indent though. The 8rt engine should give me the aluminum rear seal holder and the crank snout piece. We have a houseful of guests so Ol Gramps will need some away time in the shop, which will allow me to get more pics of water pumps etc. This is my first time assembling a V8 from a mixed bag of 'found' parts so please excuse my lack of knowledge in this area. The others were complete engines that I put back together with the labeled parts that were removed, cleaned and painted. Looking through some Old pics I see this engine that came with a bunch of stuff frome East of the cascades. In a weak moment I sold it for 500 bucks to defray the cost of the trip and the missed two days of work. What a dunce....

[GB SISSON]

This forum is such a great resorce with all this help. I should be able to come up with two of those water pumps and if they seem good I'll use them. Ol'Ron put it well when he suggested that the price can spiral outa control so quickly when doing something like this, so for the most part I will use what I have and buy what I have to.
Now it's time to paw through my stack of flywheels. I remember the new clutch thats been in the woodie for about 2000 miles is a ten inch. I also recall that the holes in an 8ba flywheel are drilled clear through. Wish me luck on my ongoing treasure hunt.

[GB SISSON]

From ten flywheels I found 2 8ba's drilled for 10" clutch with good ring gears and a 10" disc. I also found two more cast bell housings, four oil pumps, and a large number of exhaust manifolds, late intake manifolds and ported carbs. I know some prefer the original ford pumps over reproduction parts. The two setups pictured have similar overall length. Would these be correct for the truck pan?

[38 coupe]

The short pump was the last, best, design from Ford. It should have helical gears in it that makes for a more efficient pump. It is such a popular pump to use in all flathead rebuilds that new copies of the short body pump are still made today by Mellings. It looks like the pickup tube on the pump is the correct one for a truck pan. It is easy to check, slide the pump into an empty flathead block and set the truck pan without the clean out plate on top. The pickup cup should line up with the clean out opening.


Keep the pictures coming, this is kinda fun.

[petehoovie]

Originally Posted by GB SISSON

From ten flywheels I found 2 8ba's drilled for 10" clutch with good ring gears and a 10" disc. I also found two more cast bell housings, four oil pumps, and a large number of exhaust manifolds, late intake manifolds and ported carbs. I know some prefer the original ford pumps over reproduction parts. The two setups pictured have similar overall length. Would these be correct for the truck pan?