Rod of Correction: 255 thou spacers for 200's,221's,250's

xctasy

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All these good old non-cross flows are missing just one thing, a set of really good rods!

On my quest to building the perfect six, I've looked at the huge weight saving on the early blocks compared to our Aussie cross flows. The blocks are 1 3/16 th narrower, and, in the States, have plenty of Tempo/Topaz rods and pistons to choose from. So they are good building blocks to in-liner supremacy.

While trying to get the adaptor plate for cross-flow heads to US blocks sorted, I mesured the stock piston lands, and found the rings stopped short about 275 thou short of the top of the block. In most cases, having a rod about 275 longer would help make a good deal more power and improve the rev range and smoothness. So I think a 250 thou spacer plate, made of steel, will allow the following for these engines:-

1. 200, add 255 thou plate, and use 2.3 HSC pistons and bushed 2.0 Pinto rods. Grind down the crank 79 thou to fit the smaller 2.0 Journal. Gives a 5" rod, 1.6:1 rod ratio (5 / 3.126). The rings will come up to the top of the block, and stop short just before the old 7.808" deck height mark, with the piston top held within the 255 thou spacer. Need to find some pushrods which are about 8.1 inches tall.

2. Aussie or Argie 221. Use a 255 thou plate, add 5.45" 2.3HSC rods from a Tempo, and use its 1.500" tall pistons. This gives a nice long rod for a 5.45/3.46 or 1.58:1 rod ratio, much better than the 5.14" rods used as stock. For pushrods, just use the 2.3 Tempo/Topaz (they should fit as the cam shaft is in the same relative position as the 2.3/2.5 engines).

3. 250 engine with 6.21" 300 cid Big Six rods, with bushed wrist pin, and a set of 1.5" 2.3 Tempo/Topaz pistons. A nice 255 plate will keep the piston in the block, and give a 1.59:1 rod ratio, much better than the stock one. For pushrods, any ideas?
 
no idea as for pushrods on the 250 option mate,

but i think you may just have a little too much extra free time on ur hands :P :P :lol: :lol:

cheers.joe.
 
Yeah, pehaps I do, Joe. But this idea came to me while logging bags of pavement from a failed section of road. Guess I need a bigger project to keep my mind on the job!

SR, the idea of sleaving it is a really good one. The blocks will take 60 thou over bores to use a sleave that gives you a stock bore size. If the spacer was about 740 thou on a 200 cuber, you'd fit a 2.3HSC rod and piston in there. The weight penalty would be about ~27 pounds, from memory.

Do you think the split line on a thrust face of the outside of the liner will be a problem? Like, the top part will not be cooled, but the area below will be. I've heard, from a Hot Rod article in 1988, that the Ford big block dudes from places like Georgia run spacers up to 1.7" thick for the fat 600 cubers they used to build before taller SVO '385' blocks came into being. I'm sure they must have sleaved the block to do this.
 
From what Martin said Argie SP racingengines were destroked to get a better rod stroke ratio, not sure what rods they are using but it's probable that they are custom rods. I've tried to look stuff on the web that at least explains a little on the set up of these engines but found nothing so far. These guys are very secretive of their set-ups (can't blame them) Maybe you can figure out why the 188 size was choosen, I believe they use the same 93.5mm bores like the US 200 do.

Alex
 
188 CID with a 3.68 bore works out to a 2.94 stroke. To get a zero deck with a 7.808 deck height and a standard 1.511 compression height, you'd need a 4.828" conn. rod. Anybody want to guess?
 
Working from my admittedly flawed memory, i thought the 170 had a smaller bore and stroke than the 200- and i seem to recall once having put the 170 crank in a 200 on desktop dyno and ran a curve. IIRC the displacement was 188 ci.

So maybe a 170 ci crank? I thought I heard (w/ same flawed memory) that they did make 7 main 170's
 
And another thought-

If you're going to the trouble of a special rod, why use a stock compression height? Stick the rings up at the op of the piston, and move the pin up.

Defeats the whole intent of this thread, but you may be able to get another 3/8 inch or so in rod length. Gets you into the 5+ inch rod length zone- with a 2.94 stroke, you'r up in the 1.7:1 range
 
Yes, the 188 was a clever piece of re-engineering. Keep casting those 170 cranks, and put them with the new 221 blocks. Voila! Two new (larger) capacities, one block, two cranks and rod sets...

Adam.
 
Aussies got into seven bearing Pursuit 170's and 200's in 1965, with 3.5 and 3.68" bores. They carried on until the XT in 1968, when the 188/221 got released. In the US the Mavericks ran a seven bearing 170 in 1970, I think. These engines only lasted till 1971 when the XY cam out. Then Canadian Bill Bourke ordered rationalisation of all engine lines to a one-size fits all block for the sixes (200/250 only, 9.47" tall) and V8's (302C/351C with 9.206" tall block). The first 200 XP block carries the same bellhousing as the last 1991 XF Ute 250...they made no major changes for 26 years!

A 73% increase of capacity from October 1959 144 to the first 250 cuber in 1969. All via a 1.41" stroke and 0.180" bore and 1.661" deck increase. The little Canadian built block has been built in from the deap south to the far northern Americas, and even in Down Under, and still forms the basis for todays 321 hp Turbo Falcons. A few pieces of steel on the block of a non-cross-flow and mixing a few HSC bits is in keeping with Fords 'lets scramble' philosphy!

The 188/221's:-

The rods for 188 were 5.37 to 5.40, and for the 221, were about 5.11 to 5.14" Stock 170 cranks for the 188, as Adam said, and stock 200 cube pistons on both blocks.

The block was totally the same, just a crank swap. Another Ford has a cheaper idea. Argie guys use the 5.37" rods in the 221's, and possibly a custom piston or nice thick copper gasket and longer pushrods, I guess.

Notes:Rodger Huntington noted Fords pre-ocupation with spreading (amortising) tooling costs over a wide range of engine lines.

Fords Lee Morse and Bill Miller and a good deal of other production engineers were playing automotive 'scrambled eggs'. The same concept gave Windsor 289 blocks 351Cleveland 4v heads and a forged steel 302 crank to create the 302 Boss. The 400 Ford getting a 351Windsor-style crank to make a 351M, a 351C getting a 302 stroke crank and 351w spec rods to make the Aussie 302 C, the post 1980 Windsors getting a 351C fireing order. Or the 302 getting a debore with 250 pistons to make a 255 Windsor 4.2. Pick and mix. 385 (370/429/460) and 335 (302C/351M/K, 400) engines ran the same dissy's and valve gear, similar balancers and even 302Boss water pumps swapped into 335 blocks.

Head spin!:-

The 188 cube and 221 engines ran the 8.425" deap block, with a 250 Falcon cam spacing, about 1/8 th of an inch furter out to suit. The extra 617 thou gave a worse rod ratio on the 221 than the stock 200, while adding about 30 pounds to the weight. The pan width changed to suit the stroke increase, with an Aussie 250 width of 9.685, up from the 9.29" of the stock 200 short deck. The mains were 200 size, and all were seven bearing. The US 250 was wider still by about 0.5". All because the Aussies wanted to use the smaller 200 bits on the 221 and 250 blocks. Clever beggars!
 
Twentyover is right. If you are going to the effrot to put longer rods in you might as well run custom forged pistons.
Here's a few ideas for longer rods-
For a 200 use 5.205" 2.3 pinto rods (available aftermarket crower, eagle, etc.) offset grind the crank .080" for a 2.97 stroke, 1.12" C.H. custom pistons. That makes 194 cu. in. and a 1.75 rod ratio.
A 170 or 188 crank in a 200 block, use the same rods, offset grind .080", 1.20" C.H. piston= 2.80 stroke, 183 cu.in., 1.86 rod ratio.
For a 250 use 2.6 mitsubishi rods (6.535") came in all kinds of mopars, these are beefy rods. Offset grind .040" for a 3.83 stroke, 1.02" c.h. piston, 1.71 rod ratio and still have a 250
All cu. in. are with a .040" overbore
 
Great calcs. The idea I had was to offset the cost of 'forgeries' by just the cost of machining up a spacer and adding some better rods. Believe me, 1.2 to 1 inch tallforged pistons are not cheap, especially if they are not Chevy SB or Pinto sizes. However, I went to SBC forged V6 ones for my 228, and even pre-owned and un-used, they cost an arm and a leg. The deck machining and gudgeon pin changes pushed me over the edge. So possibly a custom rod is a great idea.

A stock or oversize cast piston possibly won't need all the intellegent reworks to fit the rods, crank and pistons together to clearances which won't be all Mitsubishi, or all Ford anymore. The offset grinding isn't so easy because there my be more in balancing than removal of metal from the crank.

The ideas you have, Twentyover and heXhead, are real winners. I'd love to bench race a dollar combo. If its top quality, then nothing should go wrong, right?
 
Bench Racing's quick and cheep, and so am I

The intent of a longer rod and better rod ratio is to make a motor that spins, and, if you're going to the trouble to get a motor to spin, I'd put a forged slug in it.

On another board I'm on there's been talk about stroking a 2.8l Ford Cologne motor and using a subaru piston. Stock bore size there is (IIRC) 3.65"- I'll need to look, but the hot rumor is that this has a short compression distance. Maybe no CUSTOM forged pistons.
 
2.8 Cologne engines have:

a deck of about 8.08",
with 5.14 inch rods,
2.7" stroke
and 3.66" bore
for 2793 cc's.

The block can take a reasonable overbore, and the 4.0 Explorer crank can be made to fit. The type of cams, ignition and front cover timing gear is based on the 2.9's chain driven crank, but the earlier 2.8 block and stuff can be made to fit the later configuartion crank. 3.7 litre stokers used to be made by the chapter 22'd Powertune in England for there Sierra XR4i (Merkur's ) with these US cranks and forged pistons. The right 1.28" Subaru piston, which has the right pin size, allows the use of the stock German 2.3/2.6 Capri/Taunus/Cortina rods, which have a bigger rod journal than the 2.8 rod, which is 2.0 Pinto size at 2.047 rather than 2.126 like the 4.0 and the 2.3. The 2.6 Capri is not too rare to find, and that would save having to turn down the 4.0 Explorer crank.


There is a bit of work to it, and you sure don't want to use the stock fibre cam drive unless you have a few spares about. But the US market 2.8 has good heads, a tough block, and an aftermarket support which is quite tunned in.

It was cost that made me bail on my 2.3 Cologne Cortina. I wanted the same sort of stroker. I think you are onto something 'big'.
 
Didn't intend to hijack thread to V6 cologne motors- what I didn't clearly indicate was that the scooby piston had a shorter compression height and approximately the same bore as a 200- so maybe some joy in a nearly stock piston for a long rod motor- maybe a 5 inch rod w/ a minimal deck cut to zero deck height.

NOW a shameless plug for the Cologne V-6's

Spent a bunch f time talking to the Capri Yahoo group and it looks like I'm goint to put a 2.6 intake on a 4.0 w/ shims between intake and heads to address deck height differences.

This would let me run a carbureted 4.0 to replace the 2.8 in my Capri II in the Republik of Kalifornia, land of fruits, nuts, recalled guvnur's and other circus acts. All this work in the name of 'Clean Air'. If only it was as easy to run injection w/ our smog laws
 
The idea sounds good. Imagine you could sleave six cylinders in the US for about 300 notes, so the slightly smaller, short deck Scooby piston can fit a 5" Pinto 2000 rod (which doesn't has the same gudgeon pin diameter as the Subaru, means it would need bushing of the wrist pin) for little extra on the cost of custom pistons alone.

And then I could take this higher rev, almost 200 out for a thrashing, yeah?

Still harping on a little, do you think a much longer sleaved block, with a smaller Subaru bore, approx 485 thou thick block plate on the top of the bores allowing space for a 5.45" con-rod from an HSC 2.3 Topaz, whould be cost effective? I'd have to bush the rod to fit a 33 thou thick bronze push, would that be cost effective?

From this source

Description | Rod Length| Rod Big End Bore |Crank Rod Journal | Rod Big End Width |Wrist Pin Dia| Crank stroke| Piston bore| Piston CH|

Subaru 2.0L 2001+| 5.135â€￾ | 2.165â€￾ | .840â€￾ | .905â€￾ | 2.953" |3.622" |(92mm) 1.287" |

Toyota 3RZFE (2.7L 4-cyl) | 5.785"| 2.204" | 1.016"| 0.945" (24mm)| 3.740 (95mm), no other info


As for the Toyota Previa 2.367, no other info, although with a to-the- water-jacket over-bore it will fit a 3.8" bore
 
If I were to build a plate like you're suggesting, the only way I'd consider it would be with a sleeved block. I just believe that's the best way to prevent any real cylinder sealing issues.

Another alternative (for the really long rod boys) is to build the spacer plate from aluminum, make it about an inch thick, and run a 250 rod (5.88) for a 1.88 rod ratio. Since you've sleeved, there should be no reason an aluminum plate wouldn't work, and since you've sleeved, the machine work may be less difficult.

Bore the block, step the OD on the sleeve, and install the plate. Use two head gaskets, maybe dowel in a couple more places, just through drill water pasages. Stll about 30-35 pound weight increase, and an additional inch high- maybe hood clearance issues, maybe not

You know, I didn't want to start thinking I might want to do this, but now that I'm thinking......

With the 2.94 stroke 170 crank, you're at 2.00 rod ratio. My motor has a set of forged pistons (a set of TRW's purchased about 25 years ago)- this thing has a potential rpm ceiling of 8150 (based on piston speed) if the bottom end is properly prepared.


Hm....
 
My machinist and I did a bench racing exercise on what it would take to build a "big bore" Ford six using sleeves.

Going thru his book of available sleeves, there are several alternatives. The biggest one we could fit was limited by having a reasonable amount to space between the cylinders. Looking at some of the Honda engines ye had in the shop, we figured that if we could keep as little as .080" between cylinders, we would be ok.

Based on that, we calculated that we could use a .200 thick wall 3.9" bore sleeve. You would completly bore away the old cylinder and insert the sleeve in its place. The bottome of the block would be stepped to hold the sleeve which would be a wet liner. The size of the bore would require you to siamese the cylinders. then you could bore it to a max oversize of 3.96" leaving a healthy .140" wall, except in the siamesed section.

Displacement for a 250 done this way with a .090 offset crank grind to an even 4" would increase to 296 CID.

At this point you would have spent $5000 in materials and machining just to get a usable block. Another $5000 and you might have an engine that's just as large but more fragile than a 300. It would be money better spent to start with a 300.....

But....I think the biggest sleeper six out there has to be the 240. With a 4" bore, short 3.13" stroke, long rods, pretty good head, and stout block, it would have to be a great revving, powerful engine. A little tall, but not much more than a 250.
 
I already have a 200

My problem is that my wife thinks that i should use that parts I have prior to getting additional parts.

Foolish girl doesn't understand the essence of 'car guy'- ness
 
Wow Jack. You really have been thinking!

That 240 is quite an engine. I think, because I'm so preverse and contrary, that it would have been the engine to fit in my Falcon. The head can be made to breath properly, it just needs a little help to get rev-happy without loosing too much low end torque.

Technically, a wide bore spacing engine with about a 1.7:1 to 1.8:1 rod ratio triggers the optimum performance. It doesn't have to be short or undersquare to rev, but it helps.

A 240 has an L/r ratio of 2.07:1 or so. Possibly to much weight hanging out in the block for the capacity. The 300 is rather restricted by the rod ratio, but with some kind of 6.86" rod and Scatt 347 SBF pistons (1.15"), it would eat anything with the right carbs and cam. When you compare a 400 SBC with a 400 BBC, the big-block has more power. So it is comparing a modififed 250 verses a bored out 240. The wider bore allows less valve shrouding, more piston area, and better poerting to be used. An alloy head or SOHC/DOHC engine in the 240 to 250 cube range would breath better than a stockish 240, but the 240 has more potential for revs and power if the heads could flow as well.

Never mind, downsize the car, and copy Jack mode. Sleaved 200's all round? Or maybe this weird 'flitch plate and sleave' idea is best on a 300 six, with a set of 4.22" sleaves, that offset ground 4.375" crank Clifford did a few years ago, and 367 ci, 6 liter in-liner.

Try that in your Mustang!
 
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