Stroking a 200

[Anonymous]

Hi, I'm looking for info on stroking these little inline 6s. As I understand it, you can move the journals out on the crank to gain a longer stroke. Now, aren't there more radical stroking methods? I'm talking about using a different crank altogether. IE: Could a 250 crank be used along with shorter connecting rods and/or pistons with higher pins? Is this just plain riduculous? The math and power curves are boggling. Hell, I'm just rebuilding my first engine. I should probably keep it simple!

Davie

 

[xctasy]

I'm glad you raised this. In Argentina and Australia, the 188/221 got room for a 3.46 stroke crank by moving the cam upwards, and raising the deck to 8.425 " from 7.808". The US market never got this...the Americans did a Texas Special, and gave us the 250 with a 9.48 inch deck.


I'm not sure if the cam was furter raised on the 250 when compared to the 188/221.

You do have hope though.

Weird Idea 1001:-Take the cam out, shove in a crank trigger ignition, a 250 crank, grind the daylights out of the pan rail, and then make a cradle to hold an Aussie 3.9/4.0 SOHC camshaft in a custom built cradle. I saw this done in a Hot Rod magazine with a 350 V8. It was very cool!

Weird Idea 1002:- Take a 250 crank, shove it in the ground original crank case, and then place a steel plate 300 thou thick on the block. The grab the Aussie OHC six cylinder head, and intergate the design until it fits.

Both are expensive options. That's why the 221/250 engines exist...Ford Had A Better :idea:

 

[Anonymous]

Thanks for the info. I s'pose I could just use the 250 I was gonna take the crank from. The main reason I wanted to stay with the 200 block was because of the clearance issues in my roundbody '63 Falcon. I've heard the 250s taller deck height doesn't leave much room for the carb and air filter. What are your opinions on the 250 vs the 200 as far as performance options? It seems I hear people opting for the 200 much of the time when they have a choice.

Davie

 

[xctasy]

Well, the 200 is a really light little engine that outlasted the 250 by four years or more in America. It has much better parts availibilty, and is able to take a lot of punishment while still fitting in your car.

The brawny 250, if its a US, is wider around the pan, and needs custom mounts to fit, along with a slim-line radiator and some extra thinking over the fan. Small block trans bolt pattern, lots of extra weight. The Aussie 250, log, 2V or cross flow, packages only slightly better, and has the earlier four bolt block pattern. (I'm not sure if it is the same bell patern as the US post 68 200 block, but its similar). These engines have real power and torque on the street in a light car.

The Argentine/Australian 221 is the best retro-fit, but they are hard to find in the US. Importing a 221 from either country has been done, and it packages really well. There is an inch less deck height to the block than a 250, and 0.617 inches more engine height than a 200. And the Argie engine mounts are still being made. This means the water pump and harmonic balancer are less likely to intrude as they do on the US 250.

The 200 is the best choice for a 63. The 18 year production run has garnered a wealth of info, and a hot one with a good carb is sweet and can haul some good figures if you are prepared to work it a little. If you break anything, there are parts for it.

 

[addo]

If you're rebuilding an engine to swap in, I'd say think hard about a crossflow with alloy head. Actual rebuild costs will be very similar, the core purchase price reasonable, and you will have a light engine with excellent power.

As XE mentioned, the 221 is a good motor, small, light and can really scream with triple carbs. But truth is the crossflow will outpower it, and easily. If you stick with the smaller engine, a turbo is often a good way to push it harder.

Adam.

 

[Anonymous]

As usual, addo is dead nuts on...!

Add a turbo to a late model (large log, low compression) rebuilt 200 and you'll have the best of all worlds -- great revving engine that fits the stronger V-8 trannies, high torque from low RPMs, and wow! factor out the a$$...

 

[Anonymous]

Cool enough. I have a '66 200 in the car car now with about 20,000mi on it. It runs quite well. The rebuild candidate is what I took out of the car after I bought it; a '66 block with a '75 head. I want to rebuild this engine with some nice parts and get it well balanced. I'm sure the '75 head will do much better than the '66 head. A nice cam, exhaust header, better carb and drivtrain and I'll be movin!

The stroking was just one of those nutty ideas that you've got to check out. Thanks for all the input!

Davie

 

[Anlushac11]

8)

I already have a '80 Stang with a 200.

But if I was starting from scratch I would do a US 200 with Jacks crossflow head mod.

Bulletproof bottom end that revs like a Jaguar and a lightweight aluminum crossflow head that will let you crank some serious power out of it.

 

[xctasy]

Lets hope the 200 Locost kit works. Its like a good version of the Cuban Missle Crisis...the Six cylinder Ford world is holding its breath!

If the Alloy head to 200 block works, you guys have it made. Imagine a stock 5.0 GT getting a high rev Maverick/Granada 250 with alloy head and EFI as a hop-up. Insane!

 

[Anlushac11]

8)

If money was no object type ofd thing:

Import a Krogdahl DOHC head, use a electric fuel pump and invent a crank trigger and DIS.

Then there you could remove the cam from the block and stroke away.

Actually once i get back to work Im still running the idea of a 221 through my mind. All I would need is a C4 bellhousing and a rear sump oil pan.

 

[Anonymous]

Hey, Linear - don't miss this trick - contact Dave CZLN6 and get his Falcon Performance Handbook before you take another step. It will save you LOTS of do-overs like mine .

 

[xctasy]

Yes, thats right. I've used the excuse that I've had an Aussie six, and the book doesn't count. From what others have said, it is of unviersal importance. Its the Bible on which you need to base your ambitions. A little knowledge is a dangerous thing, but all this other talk of strokers and heads is sort off out there, you'd agree .

We "Aunzies" are just a little taken by the fact that there are serious six cylinder gear-heads in America as well. 8)

My advise. Buy the book, get into the basics, under stand them, create a firm base. Then turbo the heck out of it if you get the chance!

 

[Anonymous]

Actually I believe you could stroke a 200 by offset grinding and using some honda or toyota rods. The smaller diameter of the rod big end would probably leave some room for clearance. But its not worth the trouble for a couple of cubes and you'd still have a bad rod ratio.
What I want to do, and I know this is probably against conventional wisdom, is de-stroke a 200. Take a 170 seven main crank, which so far does'nt seem to exsist, de-stroke it by offset grinding down to a 2.80" stroke and run 2.3 ohc rods. With a 1.86 rod ratio and a good flowing head with a valve train to match you'd make some serious high rpm n/a horsepower.
I'd be prepared to build this engine if I could find the crank.

Franklin

 

[addo]

170 seven mainers are plentiful! The 188 was a 170 crank on 200 bores.

Adam.

 

[xctasy]

That's right. And you can easily use Holden XT5/Starfire (5.25") con-rods to do an offset grind to a 1.9 or 1.88" journal. The issue is finding a 923.314 to 95 mm pistons (3.68 to 3.74, or up to plus 60 thou on the stock block). Ones that are 0.954 or 0.825 inches tall. The lowest I've seen is 1.075" in the Ross or Wiesco pistons. You'd need a spacer plate or copper gasket of about 125 thou for the block to fit the the Holden rod. The GM rods are bullet proof, and would just scim past the cam and pan rail. With a 95 x 85 mm bore X stroke, that'd give you a US 221 from a 200 cuber with the same block. 420 thou or so shorter than an Argie or Aussie 221.