221 block bore size

[kurt v]

What does the bore mic before the sleeve is installed in a 221 cu in block and weren't there pistons made to go into that 221 block with sleeves removed?
I lent out my ford mag and didn't get it back, a last fall issue that had a write up on pulling sleeves and what pistons to put back in.
clear as mud ?
thanks kurt

[Mart]

.083" if they are the factory installed "tin can" sleeves.

Purely from memory if someone can confirm that would be good.

[Ol' Ron]

MARTS RIGHT!! yOU CAN GET PISTONS THAT SIZE FROM vAN PELTS. sORRY about the caps, can't see this far anyways.
Gramps

[kurt v]

Ron i was just looking at your book and i see .001 to .003 will give me just what i need and i have Mac's parts book to order from, the .080 over piston with sleeves pulled should work out just right.
thanks kurt

[kurt v]

Ron, that's Mac Van Pelts parts book that i was looking at.

[bbrocksr]

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Originally Posted by kurt v

Ron i was just looking at your book and i see .001 to .003 will give me just what i need and i have Mac's parts book to order from, the .080 over piston with sleeves pulled should work out just right.
thanks kurt

.083 is right but sometimes the bores are pretty rough after the sleeves are pulled, might take a lot of honing. You can always bore it to 3 3/16 and use stock 3 3/16 pistons.
Bill

[Steve in Denver]

so is the wall thickness the same on an 8BA sleeve?

[Ol' Ron]

The .080 piston is smaller than the.083 piston. Cakk Max and ask him
Gramps

[bbrocksr]

Originally Posted by Steve in Denver

so is the wall thickness the same on an 8BA sleeve?

8BA didn't have sleeves originally.
Bill

[KiWinUS]

Originally Posted by steve in denver

so is the wall thickness the same on an 8ba sleeve?

no. No. No

[Ken/Alabama]

Originally Posted by KiWinUS

no. No. No

Tony is correct !! You didn’t say what year 221. I just bored my 40 221 to 3 3/16 and installed std merc pistons with a merc crankshaft. Runs like gang busters !

[alanwoodieman]

running that engine right now-- stock 239 pistons in a bored out/sleeves removed 221 block

[Mac VP]

That’s our usual advice for the 221 cubic inch blocks (39-42 variety)…….remove the sleeves and bore it out to 3-3/16”. Assuming there are no cracks requiring repair sleeves, and that a simple sonic test of cylinder wall thickness shows that there’s no weakness in the walls, this makes more sense than buying 0.083” oversized pistons and rings. Those are now quite expensive and we consider them to be “special order”. Moving up to 3-3/16” bores means you can buy regular 8BA pistons and rings (Standard size) which are much more reasonable in price and generally available from stock. You can still use the original type connecting rods and crankshaft if you want to.

[kurt v]

Got good at knocking the sleeves out, 4 sleeves less than 25 min, no scored cyls. Going to get it bored so i can use the merc crank and rods i've had for almost 30 yrs, now bore it stock or how much over?
kurt

[38 coupe]

Bore to stock 3 3/16 inches. With good clean water passages it will run with plenty of power and also run cool.
I am in the camp that advocates surfacing the heads to get 0.050 over the piston.

[Mart]

Is there a gasket made that suits a 21 stud with 3-3/16" bore?
What do you guys use?

[38 coupe]

I don't know about big bore 21 stud motors. I thought we were discussing the late 221 motors that are 24 stud, the 38 through 42 USA Ford engines.

I'm guessing an enterprising individual could make a big bore 21 stud gasket by taking a standard 3 3/16 bore 24 stud gasket and adding the four stud holes bellow the cylinders by using the correct size hole punch. I have no idea how close to the stud the bore gets though.

[Mart]

Originally Posted by 38 coupe

I don't know about big bore 21 stud motors. I thought we were discussing the late 221 motors that are 24 stud, the 38 through 42 USA Ford engines.

I'm guessing an enterprising individual could make a big bore 21 stud gasket by taking a standard 3 3/16 bore 24 stud gasket and the correct size hole punch. I have no idea how close to the stud the bore gets though.

Ah ok, yes, in that instance, no problem. It wasn't stated which 3-1/16" bore motor was being discussed.
Were the 24 studs the only ones with the tin can sleeves? Or did the 21 stud motors get them also?

[38 coupe]

Originally Posted by Mart

Were the 24 studs the only ones with the tin can sleeves? Or did the 21 stud motors get them also?

That is a great question. In the USA I *think* only 24 stud motors got the tin can sleeves, but I could be wrong (this is Ford we are talking about here). My knowledge is limited when the subject gets to overseas production.

[Bored&Stroked]

I'm not aware of the usage of the "tin can sleeves" on the earlier 221 cubic inch 21 stud motors.

With that said, Henry didn't like to junk blocks - so there are almost always exceptions to the rule! LOL

[kurt v]

24 stud 39 to 40 block large crank