Sleeve Block W/ Rised Intake Need Info.

[HOTROD_WILLIE]

Got this block the other day. It is sleeve block w/ rised intake. I under some people like these block to hotrod. I would like know the history of these block. Plus the avenge of using these block. Thanks for all the help.

[JSeery]

That is most likely a 41-42 block:

"1941 feature some detail changes compared to all the previous 221 and 239 cubic inch V8 motors. The freeze plugs in the oil pan were eliminated and the intake deck is no longer flat. This is referred to as a raised intake block, but actually the intake is the same height and the surrounding area is sunken a bit. This was probably done to save a bit of cast iron and prolong cutting tool life. Another interesting feature of the 1941 motors is the outside wall of the block that the exhaust ports exit through. 1932 through 1940 blocks are flat with raised exhaust ports. 1941 blocks are curved between the exhaust ports. The 221 and 239 cubic inch blocks can still be differentiated by the center water holes in the cylinder head decks." (copied from a pervious post on the Barn).

I like these years for the looks, other than that, I am not aware on any advantage as compared to a 46-48 block. It is my understanding that the later blocks (46-48) are more desirable.

It is also possible that it is a "War Years" block, not sure there is much information on flathead blocks for the years 43 through 45. Any information on where it came from or what vehicle it was originally in?

[JSeery]

The above referred information was from Fred Mills. Not sure about the water holes shapes between the cylinders.

[Tim Ayers]

From what I recall, aren't these the blocks that generally found to have more meat in the bores? If so, these are a desired block; especially for roundy round guys.

[G32]

Originally Posted by HOTROD_WILLIE

Got this block the other day. It is sleeve block w/ rised intake. I under some people like these block to hotrod. I would like know the history of these block. Plus the avenge of using these block. Thanks for all the help.

Willie: Check to see if your 41-42 221 doesn't have a full set of
heavy wall cast iron repair sleeves (FMC remanufactured ?) rather than
Ford's .040" thin wall steel sleeves. Bore size? Rods & mains sizes?
See if there are rebuilder's size stamps on outer edge of 1st crankshaft counterweight.
81 (39-42) cranks had 2" rod journals. Rod cap Cast "s should be 91
or 21.
Hey.. good picture showing concave rather than flat block (41-42)
sidewall; also no casting core hole bumps above pan surface.
My opin--try to clean up bore & use with minimal change; want bigger, start with 239 engine.
Have fun with them!
Gene Tulsa

[bbrocksr]

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Originally Posted by G32

Willie: Check to see if your 41-42 221 doesn't have a full set of
heavy wall cast iron repair sleeves (FMC remanufactured ?) rather than
Ford's .040" thin wall steel sleeves. Bore size? Rods & mains sizes?
See if there are rebuilder's size stamps on outer edge of ist crankshaft counterweight.
81 (39-42) cranks had 2" rod journals. Rod cap Cast "s should be 91
or 21.
Hey.. good picture showing concave rather than flat block (41-42)
sidewall; also no casting core hole bumps above pan surface.
My opin--try to clean up bore & use with minimal change; want bigger, start with 239 engine.
Have fun with them!
Gene Tulsa

What is the bore size? 41 Ford ,3 1/16 =221- 41 Merc 3 3/16 =239
Bill

[scooder]

It's a 221ci 3 1/16" bore, appears 0.040" thin wall lipped sleeves.
If I recall, Walt has taken these out to 3 5/16". You can also bore it 0.080"ish and fit standard 3 3/16" pistons for 239ci.
Its not the real thick walled 99A Merc/truck block, those are silly thick, ridiculously so.
Still a nice block though.
Martin.

[Walt Dupont--Me.]

From the pic I'd call it a 42 block, no core plugs in the pan rail, It's hard to tell if has the steel .040 sleeve or the unaversle cast 1/8 wall sleeve. If it 3-1/16 with the steel .040 sleeve I've removed the sleeve and bore another .045 to 3-3/16 and use the A heads, makes good compression. You might tell it it's has the thin sleeves by looking at the bottom of the cyl. Walt

[scooder]

My bit should say bore 0.045" for 3 3/16" not 0.080 ish, didn't have my head screwed on properly.
Sorry if I confused anyone.
Martin.

[Bored&Stroked]

Hey Willie: That appears to be a Ford block - with the thin sleeves. What is the current bore size - probably 3 1/16 (221 cubes). The 42 Merc engines were 3 3/16 and have the same keystone water passages, non-sleeved, etc..

If you're going to big cubes, this is probably not a block that you want/can bore very far. With that said, you can pull the sleeves and have the block sonic tested to answer the question of how far can you bore. I don't believe in any hard and fast 'facts' related to block thicknesses in general - have seen a lot of variations in the earlier 24 stud blocks. Lots of myths and lots of blocks have had a 'rusty' past - each one has it's own story to tell.

Block Strength: I've heard some say that the 59x blocks are stronger and less prone to cracking (especially in the transfer area). I've also heard others say that they believe the ultimate block is a 42 merc (pre-59x). Who knows - probably related to the individual experiences of the beholder. To me, if you're not going totally wild on porting, bore-size, cubes, etc - use what you have!

From a performance perspective, if you have a good block - it can make a fine performing flathead. You can build a very nice engine based on a 3 3/16 bore, throwing in a stroker crank to get some more torque and cubic inches. Most folks are really not drag racing their flatheads and 'ultimate performance' just isn't the goal - streetable performance, reliability, sound and looks seem to be the most important these days.

Have it cleaned, magged and then sonic tested - either you or somebody else will use it if it is a good piece.

Best of luck,

B&S

[HOTROD_WILLIE]

Thanks everybody for the information. I am building a warm over street motor. The sleeve has no wear. I am leave them in. Hope to start the build this summer.

[Ol' Ron]

Definitely a good block, if not cracked. Go with what Walt said. I've punched these to 3 5/16.

[scooder]

The Merc blocks have a round central water hole.
Martin.

[G32]

Originally Posted by scooder

The Merc blocks have a round central water hole.
Martin.

Right. Thanks Martin.

Gene Tulsa