Technical Flathead I. D. please

I made a deal on an unseen flathead. My pal said he pulled it out of a 1950 big truck then had it rebuilt by a local, reputable machine shop. Yesterday we got it out of it's hiding spot. It definitely was rebuilt, new adjustable lifters and minty clean in valley. Maybe I got lucky.
I took a few pictures, any help would be appreciated.

 

This is where we extracted it from

 

Simply is a 8BA that everyone has..... you can tell by the timing cover ..... probably better off to trade it foe something earlier.

I can offer free shipping if you want to send it.

 

Very nice! Looks like you’re no stranger to flatheads. Lol! Are those grade 5 head bolts?

 

Someone needs to help the man clean / re-arrange. On the left i see the wheels/rims stacked with rags between so his intentions must be good but the other stuff is overwhelming.

 

Wheeldog, Great find. Thankfully the seller remembered it was there. One quick point: one head marked EAB from a car and the other 8RT from a truck. IIRC, they may have different compression ratios but this can be researched pretty quickly to see if it’s consequential.

Appears to be painted Mercury color. Realize it’s just paint but Wonder if there could be a 4” crank hiding in there.

 

Grade 5 is OK, they are only torqued to 55 lbs.

 

that is a full-on hoarder.

Nice score, the engine should make some old hot rod happy again

 

Ron your engine has one high compression head and one low compression head. Late flathead heads from low compression to high are:
8cm, 8rt, 8ba, EAC,EAB. so basically you have an 8ba for the sake of discussion. It would be nice to pop a set of matched EAB heads on there.

It would be helpful to see inside anyway. See what size pistons and check the stroke for a 4” crank. Even if it’s 3 and 3/4 you’ll have fun with it. Good luck

 

Thanks for the input fellas. I appreciate the heads up on the heads, haha. Tonight I pull the heads and pan.

 

I've got one low compression and high compression head and the thing runs smooth his silk and I don't think it makes much of a difference.

 

I pulled the heads. .100 over pistons and 3.75 stroke. Minty minty clean and no cracks, I'm happy. Do these measurements make 255ci?

 

looks better with all that aluminum on top!

 

The 255 Merc has a 4" stroke but looks like you bought a nice motor! To run the early heads you have on it you have to plug two water passages in the block and one on the head. The two holes in the water jackets are at the front of the engine, you can see them in the pictures, 1/8' brass plugs just have to run a tap in and put a little sealer on them.

 

My math tells me you’re now at 255 having picked up the additional 16 CI with the larger bore. Mercury CI with a Ford crank.

 

Scored another EAB head and sent my Offenhausers to the shop for a spark plug heli coil. So, i have options.
F- that, im putting the aluminum heads on. What are your thoughts?

 

EAB heads are pretty good. Aside from the looks, the aluminum heads may not get you much improvement. After looking all over for a pair of Ford made aluminum heads for my Mercury motor without success, I decided to mill a bit off and aluminum coat the cast iron Mercury heads I had.

BTW: is that other flathead your second?

 

Be sure to use the correct distributor that fits your timing cover.
One cover fits the short shaft distributor.
Another fits the long shaft distributor.

 

Which head is the low compression? They look the same best I can tell from he pic

 

First, remove the head gasket and clean the surface.
One indicator of which head has the higher compression would be to measure the depth of the combustion chamber at the same location in each head and see if there is a difference.
Another (and better) way would be to install the spark plugs and then fill each combustion chamber with water, keeping track of how many cc's water it takes to fill the chamber. More water means lower compression.

 

Mine

Nice score Wheeldog!

 

What shape is the combustion chamber on the Offy heads? If the EAB heads can be milled a little and yield a similar compression ratio, I would expect the factory chambers to flow better than the aftermarket ones. Even if compression comes out a touch lower, the extra flow might give more power where you want it.

A lot to study and check. Piston to dome clearance, valve to head clearance, quench. Hard to guess, harder to know what is best.

 

Thanks for the input guys, I'm learning as I go. @JD Miller the head on the right is the EAB, took me a minute to see the difference between the two. The 8RT is deeper but only by a little.
I also learned that 59AB flywheels do not fit 8BA (I got to do that twice) lucky I have a spare complete motor. I also learned that the water pumps and belt set up I was using will interfere with the 8BA distributor so my radiator will be more forward, and look guffy! @19Fordy thank you for the distributor and front cover Intel, that'll save me some aggravation.