221 Stroked 200 - Myth or Reality

Harlon

Well-known member
I’ve been searching the forum for information regarding the 221 Stroker article in the Tech Archive.
I haven’t read everything, I’m sure, but what I’m wondering is if there is anyone here on the forum that has actually built one. There are a number of threads that discuss what parts and offsets would be required but no actual build threads.

If I’ve missed something, please forgive me and direct me to the appropriate threads.

Thanks for the help,
Harlon
 
Possible use of Honda rods which have a rod bearing diameter close to 1.88, whether the rod journal on the crank could take that much under sizing.
The major problem is rod clearance & the camshaft.
Food for thought.
 
I've done the "What If" on paper using off the shelf parts and came up with two scenarios for maximum displacement:

1. Stock Ford Pinto 2.0L rod (4.977"), Chevy 334 V8 piston (3.736" Bore/1.1330 CH), and a 0.117" offset grind on the crank (3.36" stroke).
Throw that together and you get 221cid with a 0.018" piston recess. This combo has a rod/stroke ratio of 1.477 compared to the stock 1.508.

2. Stock Ford Pinto 1.6L rod (4.928"), the same Chevy 334 V8 piston (3.736" Bore/1.1330 CH), and a 0.150" offset grind on the crank (3.426" stroke).
This gives 225cid with a 0.034" piston recess. However, the rod/stroke ratio drops to 1.438!

xctasy wrote on the forum that the rod/stroke ratio of the original 221cid is 1.486. The first scenario has a rod/stroke ratio of 1.477, which is pretty close. Offset grind the crank 0.112" (3.35" stroke) and the diplacement drops to 220.3cid, but the rod/stroke ratio is the same 1.486 as the 221.

The SBC 334 piston comes in forged aluminum (ICON IC835-STD) with 2 valve reliefs measuring 10cc.
A minor problem with using the SB Chevy V8 piston is the pin diameter is 0.927", whereas the 2.0L rod has a 24mm small end (0.944"), so that would have to be addressed.

Hope this helps.
 
I only posted this last night, so I don’t want to assume too much too quickly.

But it sounds like it’s something that has been thought about a good deal but hasn’t actually gone past the “myth”/concept development stage.

Guess a supplemental question might be:
Why hasn’t it made it past the concept development stage?

Are the proposed performance improvements not sufficient to offset the cost of specialty machining and sourcing the parts?

Does the reduced rod/stroke ratio just make it an untenable exercise?

Thanks for the input,
Harlon
 
I stroked a 250, it was expensive, it was a pain to figure everything out and ended up wearing the cylinders quickly due to the short rod ration and the load I put on it. For the money you will have in the short block getting it to 221 you could buy a VI alum head even using "stock" parts, and only gain 17-21 cu. inches. Good news is the 250 crank offset ground to Honda 1.88" size no problem, so I would assume the 200 crank will be the same.
good luck
Walt
 
easiest way for 221 is 223 :shock: , go vintage :LOL:

viewforum.php?f=18

sorry, " 'is a joke, son" ('50 Sat am TV animated) Couldn't resist.

Where R U located?
Do U have machinin capacity on site?
 
chad":1871fb2c said:
easiest way for 221 is 223 :shock: , go vintage :LOL:

viewforum.php?f=18

sorry, " 'is a joke, son" ('50 Sat am TV animated) Couldn't resist.

Where R U located?
Do U have machinin capacity on site?

Guess that’s better than “easiest way for 221” is a 221 baby Windsor. :roll:
 
Just saw your question in my response.
I’m in Carlisle, Central PA. At least one old school shop in town. Meaning it at least looks like it’s been there since my dad was a kid. There’s a shop that has done rebuilds/mods for at least one member in the 40 mile range.
I would get all machining outsourced and do as much of the assembly myself. The local shop will only do basic boring, decking and standard head work. Offset grinding or any specialty stuff like a 2V direct mount will have to be done at the out of town shop.

I’m looking to rebuild to the Falcon6 specs a 78 Fairmont 200 either this fall/winter or the next. Just exploring possibilities now.
I will, if circumstances are kind, have two 78s to play with. If money is no object I’d like to rebuild both heads. One with a 2V direct mount and one with an Offy 3-1V. The spare(read not in the car and free to be machined) 200 would be machined to the manual. Once that’s done and swapped in the car I’ll have a 200 shortblock without a home.
The second shortblock could be saved for a rainy day in the event the other one fails. Or, we could play around with the 221 idea.

When I was a kid I obsessed about building a 383 stroked 350. So when I read the stuff about the 221 in the tech section I was intrigued. I know it won’t be as simple as ordering a stroker kit off line for a small block 302 or 350. But if it’s not mythically impossible or financially irresponsible, I’m game. I don’t have unlimited funds, but I do have nearly unlimited free time.
 
:shock: Yes for sure the 221's are a reality they were built and installed in many Ford's in Australia and Argentina but the rub is that they were never offered here in the US. So it's not that it's so hard to build one especially if you can get a 221 crank imported or else by modding your current crank. The time you have is good though it will still take a bit of money too build that combo. Good luck (y) :nod:I
 
Thanks fo the input.

I was hoping someone here on the forum had gone through the process and could speak to what combination of parts and offsets they used and how they felt about the costs involved versus the performance of the finished product.

Plenty of threads on rebuilding for performance on the 170, 200 and 250. Was wondering if anyone had documented a 200 to 221 build.

Maybe I’ll be the guinea pig.
 
X could line U up w/parts there in Oz.
He's Dwn Under in NZ.
May B by later?...
 
Hey, still looking to see if there is a member here on the forum that has built a stroked 200.

And just to clarify. I’m referring to the 221 discussed in the tech article archive. My understanding is that this build starts with a US 3.3l engine that is then stroked out to 221. I’m not referring to the Australian factory produced 221.

Thanks,
Harlon
 
Hi Harlon,

"...the 221 discussed in the tech article archive."

Mike W. who found this Site, Classic Inlines, the alu head in the VI catalogue'n much much more is no longer with us.
He passed away a yr or 2 ago (altho @ my age a decade is like a yr so I'm probably pretty inaccurate).

What U refer to is all laid out for U to go with. I have not been here long but do not recall any mock ups or test models.
The parts R readily available, a machine shop could follow guidelines. There R international experts here who could advise as U go...

U could ask our AZ contingency abt any developed block...
 
You also have to examine the realistic benefits of doing this and not the theoretical. The costs to do such a small gain in cubes probably won't equal a cost proportional to HP or torque that you'd actually gain.
 
can we "use some math" to look @ it a lill? -
(IDK what that would B, ahh, I don't know automotive theory)
rod to boar ratio? calculated HP or tq?, comparison to similar motors?
What could work here, doin it 'on paper'? (well 'puter these daze)

It seems Mike may have worked out the possibility in the short block & even a prts list...
to what end? I mean somebody here must have the ability to calculate results (w/o an
the actual expense of a build). May B they did that in their head (some can I bet) & have said
"Y bother?" (goin further). That seems like a reasonable place 2 start. :unsure:
(C? he's wrkin on it) :LOL:
 
Simple answer for me is: U.S. small block six 250 IS basically a stroked 200 ... .
... same Heads, cam, bearings, pistons etc, the 200/250ci have same 3.68 inch cylinder bore. Stroke: The 200 has a 3.13 inch stroke, while the 250ci engine has a 3.91 inch stroke - simple performance mods for even more torque/wider powerband. . . (144/ 2.50 inch stroke, 170/ 2.94 inch stroke.)

Specs on Aussie 221 Six were on CI spec pages.

have fun

coupl a' 250's :
.
 
"...250 IS basically a stroked 200..."
by the pros - Ford itself !
 
Jack Collins said it best....

MustangSix":1uzaelxl said:
........ 20 years ago documentation on these engine families was practically nil. It actually came as a surprise to many that there was such a large variety of blocks, heads, cranks, rods, and other components. And to top it off, almost nobody in the US even knew about all the Oz engines. That's why the crossflow Mustang caused such a stir when we put that together and tried to see where the US and Oz engines differed.

But alas, there is only so much time in a day and it never seemed an urgent thing to correct the record as we learned more. .....

BTW, I was clearing out my garage the other day and found a dirty, greasy sheet of paper with some cryptic notes and casting number rubbings that I must have done almost 20 years ago. Automotive archaeology at its finest....... :beer:


The 221 crank has a 5MA "221" part number cast on it. The 200 US cranks, 1, 2 or 3H with "200". Although its easy to change an iron crank to increase stroke, its much harder to stop it hitting the pistons or camshaft and preserve a better than stock conrod legth to stroke ratio of better than 1.51:1.


Even the 221 had the worst rod to stroke ratio of 1.486:1, almost as bad as the 400 Chevs 1.484:1. (5.14/3.46 verses 5.565/3.75)

All the tall deck stuff had the crank at the 250 Ford spacing. Even a 250 Ford crank fits in a 221 block,

20130103_173117_zps62bb97b2.jpg


like justman234's rods just clearing the camshaft



and counterweights just hitting the pistons


20130103_173306_zpse643a359.jpg



and just taking the stock pistons out of the block...


20130103_173144_zpsfd67de87.jpg


The 1968 Argentine and Australian 188/221 was designed with the US 250 cam spacing from the getgo. The 144/170/200 cam hugs the crank real close, way too close for easy stroking unless you compromise on costly pistons, rods, and smaller crank pins in the 1.77 to 1.899" diameter region. Stock are 2.124"




221 rods are 5.14 inches long center to center, (not 5.41 as perpetually, and wrongly stated elseware in the tech pages, and in other parts on the world wide web.The guy that started the Australian 250 2v revolution was this websites Aussie 7 Mains. He did most of the informative infomation gathering for MustangSixes and Mike W's blurbs, but not all of it was copied correctly, and hasn't been changed). The 188 has 5.37" long rods with a 2.94 stroke 170 crank in seven bearing form, and the same 8.425" deck block as the 221. Thats approx 660 thou taller than the shallow deck 144, 170 and 200, and the rare 187 Argentine engine, an overbored 170 with a Fairlane four bearing 200 crank.

The 188 and 221 has additionally has a cam spaced a few extra further out at 52 links. The much stronger 1971-1992 200/250 onwards and x-flow timing gear and wider link chain can fits the 188/221, but not the 144/170/187 or 200.

Fords later 1971 on wards Australian 200 and 250 runs a longer chain, as again these blocks have the cam to crank spacing further apart, same as the US 250, 2.3 HSC, and 2,5 HSO. You cannot make that space happen on a 200 block. The only way you can avoid cam to crank clashes on a stroker is by offset grinding down the crankpin diameter.Even the 200's, 221's and 250's adopted the undercut cam casting with couterweight cheeks cut out to clear the conrods. A stroked 200 needs a

viewtopic.php?t=69393
viewtopic.php?t=42698

The camshaft position is changed for the tall deck 221, 250, and 2.3 HSC and 2.5 HSO fours, which are all based on the tall deck six cylinder engines.


The 221 is 0.660" taller at 8.425 from crank center to block deck.


The Aussie 200 and 250 cubic inch engines made from 1971 to 1992 are all 9.38" tall, same as the US 2.5 HSO four cylinder.

The US 2.3 HSC engine is 8.660" tall from the crank center to the block deck.


The 200 is a bored and stroked 144, 170, or 187 cubic inch engine with a shallow 7.803 to 7.830" deck, and a tighter crank to cam center spacing which prevents stroking the stock crank beyound about 3.35" if you offset gring the crankpins to less than 1.899", you can go a little further, but 3.35" is really it. 3.48" is just possiable with the smaller Mitsubishi sized rod journals of 1.77", and with the shallowest Iapel 1.06" deck compression height pistons with a 5" rods, that's a practically unworkable 1.437;1 rod to stroke ratio.


The total amount of con-rod types for all Ford I6's of the 4.08" bore spacing familiy is six.

4.71,
5.14,
5.37,
5.88,
6.27,
6.06.

There are of course the two 2.3/2.5 HSC I4 items for Tempo/Topaz engines.
These are
5.45
and 6.00, bringing the count to 8 rods.

#9 and #10 were 1978-1980 US 250 conrods, and some 1973 to 1983 US 200 con rods, which were cast iron.


The OHC and DOHC engines had 5.88 or 6.06" forged steel conrods, and they swap in some kinds of tall deck engines.

All are swap prospects if you can find one of the 18 blocks Ford cast world wide for there passenger and truck lines. Happy hunting!

Here is my ammended A7M Aussie 7 Mains list of http://fordsix.com/aussiesixes.htm


C.I.
BORE
STROKE
ROD
YEARS


144
3.5
2.5
4.7
1960-1966
Integral Manifold

170
3.5
2.94
4.7
1960-1966
Integral Manifold

188
3.68
2.94
5.4
1967-1969
Integral Manifold

200
3.68
3.13
4.7
1966-1967
Integral Manifold

200
3.68
3.13
6.27
1970-1988
Integral Manifold

221
3.68
3.46
5.51<<<<5.15"
1967-1969
Integral Manifold

250
3.68
3.91
5.88
1970-1973
2V head

250
3.68
3.91
5.88
1976-1980
Iron X-flow

250
3.68
3.91
5.88
1980-1992
Alloy X-flow

191
3.6
3.13
6.27
1988-1990
OHC

239
3.6
3.91
5.88
1988-1990
OHC

240
3.64
3.91
5.88
1990-1998
OHC

240
3.64
3.91
6.00<<<<6.06
 
:beer: Excellent info Xctasy! One thing of interest you might add on your engine specs lists is the number of mains on the crankshafts. (y) :nod:
 
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