New Crankshafts

[t-time]

We can finally announce the pending availability of replacement crankshafts. This has been a two year project and the first sample has been running in a ’26 roadster pickup for a year with great results. The engine is a stock build with the exception of no magnets, a Waukesha Ricardo head and model A manifolds and carburetor. About 5 pounds was added to the flywheel to replace some of the weight loss of the magnets. It is running a KC Warford transmission to help with the hills in the area. The crankshaft is counter weighted, heat treated GGG-70 ductile cast iron pretty much the same as the Dubats crank made about 13 years ago. They are similar to the dimensions of a Ford model B counter weighted crank. The Dubats cranks were very successful and had it not been for the Scat forged crank coming out at the same price they probably would have continued production. These are meant to be a replacement for a stock crank and are only available in the stock configuration. Price is $1250.00 and are about 3 weeks away. Chaffin’s Garage will be the retail outlet, direct purchases will also be available from me.
https://www.youtube.com/watch?v=GwD2e4ROBiU

[dean_dorholt]

This is great news. I knew Bill Dubats and it's sad some couldn't get past the use of a cast crankshaft.
I guess my two extras Dubats crankshafts just went down in value

[Ed Baudoux]

This is great news! Thank you for your contributions to the hobby.

[Mark Chaffin]

Mark has been making great progress on this project and taking the necessary steps to bring a quality product to marked at a reasonable price. Thank you Mark for you support and contributions to our hobby. Especially in light of the fact we all have suffered the loss of alot of Model T parts manufacturing talent in recent years.

[Joe Bell]

when ever there is two suppliers of a product it makes better pricing, as in Model A cranks!

[TeveS-Nor Cal]

I would like more information on adding "about 5 pounds". Why did you feel it was necessary, etc.? Thanks

[Allan]

Have I been mistaken? When I was searching for hot-up bits for my abandoned A model Tudor project, I was told the B model crankshaft was the same as an A model shaft but with larger diameter bearing journals. I was told to find a C model crankshaft to get the counterbalanced crankshaft. They were called C models out here because of the large letter C cast in the cylinder head. This head was different to the A and B heads in that it had the water pump mounted on a vertical face at the front of the head, with a triangular stud pattern like the V8's that followed.

Allan from down under.

[38 coupe]

There is a lot of confusion regarding the 1932 through 1934 Ford four cylinder engine designation. These are B motors. The confusion comes from the "C" cast on the cylinder head. The "C" is there because of a quirk of Ford's part identification system. When the Model As were produced they had an unmarked cylinder head. During the production run of the Model A a factory high compression cylinder head was developed, the "Police Head", and to make it easy to tell from the regular heads it had a large "B" cast into the top surface. When Ford updated the four cylinder engine design for 1932 the whole engine was updated to be the Model B, and the new three bolt water pump head got a large "C" cast into the top surface. Confusing, yes? Link to a nice description of Model A and Model B cylinder heads" https://www.fordgarage.com/pages/ABcyli ... arison.htm
The "B" engines had three different crankshafts during the 32-24 production run. The first engine made through at least the end of 1932 had no counterweights. Some of the crankshafts without counterweights got press on counterweights when these engines were returned to the factory for overhaul (Ford had started a factory rebuilt program in 1932). Starting sometime in 1933? new crankshafts in Model B engines came with traditional looking counterweights. All three types of crankshafts are B cranks. A link with a nice table of Model A and Model B crankshafts: https://www.fordgarage.com/pages/rotatingmass.htm

Out of curiosity, why did you end up using German DIN specification cast iron instead of USA SAE specification cast iron?

[Cordes_jeff]

I won't run a cast iron crank in a Model T.

[Jerry VanOoteghem]

I won't run a cast iron crank in a Model T.

It's ductile iron. You could probably bend it into a "U" without breaking.

[BRENT in 10-uh-C]

It's ductile iron. You could probably bend it into a "U" without breaking.

Jerry in your opinion as an Engineer, -if the pricing was similar between the two, which crankshaft would you choose or recommend to a customer??

[Mark Gregush]

It's ductile iron. You could probably bend it into a "U" without breaking.

Jerry in your opinion as an Engineer, -if the pricing was similar between the two, which crankshaft would you choose or recommend to a customer??

This I will be watching. I am on the fence re going to counter balanced crank, but a $400 difference in price would go well in swaying me to drop some cash. (Plus I have not board my babbitt so could hold off for a while)

Ok I do have a question; Does the pan need to be dimpled to install this crank, and will the stock caps work with it?

[Jerry VanOoteghem]

It's ductile iron. You could probably bend it into a "U" without breaking.

Jerry in your opinion as an Engineer, -if the pricing was similar between the two, which crankshaft would you choose or recommend to a customer??

Brent,

I would like to see how well this new crank performs in the field. I know it's currently being tested, so that's great. I would say it would come down to availability. While a forged crank may hold an edge over ductile iron, I don't believe a Model T application will be too much for the ductile version to handle. I believe a lot of modern engines use ductile iron cranks. (They are probably a lot beefier though than a T crank...)

[t-time]

A few cranks have just been boxed for shipping, I only take money orders for payment. Email through the forum with zip code for a total. I will be delivering Chaffin's order Feb 14

[Mark Chaffin]

We are taking orders as well. Retail is the same $1,250 plus tax (If applicable) plus shipping. Nice to have options in lite of SCAT's absence.

[Dan McEachern]

Are these dynamically balanced out of the box, or will they require balancing? Just wondering............

[Dan Hatch]

How about some pictures?

[ModelTWoods]

Are these dynamically balanced out of the box, or will they require balancing? Just wondering............

Very important fact to know. Adding the cost of balancing to the crank would change the price difference.

[t-time]

They are supposed to be dynamically balanced within 15 grams, I don't have a way of dynamically checking each one.

[Dan McEachern]

Well- they have balancing holes so..... also, the units of unbalance are "weight (mass)"- "distance". ex: gram-cm etc. That IS a nice looking crank shaft!

[AndyClary]

Realistically, you buy a new crank a set of rods and pistons. You charge the magnets and replace all the spools and screws. Then you flip the flywheel back and forth while you true the transmission shaft. Checking balance isn’t really an option at that point, it’s a necessity.


Andy

[t-time]

to the top

[Aussie16]

Very nice. My engine reconditioner has always asked, Why has a version of the original Suremike been reproduced? This one looks inspired by the Suremike. Great job.

[Jerry VanOoteghem]

Very nice. My engine reconditioner has always asked, Why has a version of the original Suremike been reproduced? This one looks inspired by the Suremike. Great job.

Even if it does happen to be inspired by a Suremike, I'm not sure what that says about it one way or the other. As long as the metallurgy is correct, why does it matter what it's inspired by? I have a couple of Scat cranks in my T's. I really don't care about the counterbalance aspect as much as the fact that they're made of modern alloys, without 100 years of fatigue life in their history.

[t-time]

More like a Ford model B than a Sure Mike.

[Henry K. Lee]

Mark B.,

Nice design! Looks better than a Sure-Mike and more like an early Chevy!

Hank

[George Mills]

As to the strength/deflection/allowable stress/etc/etc characteristics compared to a forged alloy shaft Bill Dubats and I had long conversations back then. We collectively determined that his increase in static inertia due to the built in weights offset the very minor known shortcomings in comparing ductile to alloy forge at the drawing board/design level. While Bill gave up when SCAT came along and matched his price for 'a SCAT product' he lost the race on Day 2 and gave up. Might be good to know/get update on those he did produce as to how they have behaved, now some 10 years in or so.

For Mark Bruto...it might help your cause and quicken the reservations if you had some testing done on your prototype, either non-destructive X-ray or slice and dice sampling for visual awareness. All the analysis numbers in the world do not work out if you have a big blow hole bubble buried inside. That one will cause a weak spot that may, or may not, do some head scratching. Blow holes and internal porosity are a result of the process and not the metallurgy itself. A good pour with vent holes the size of broom straw is the best low volume natural venting way, then just break the stalagmites off when it comes out of the box. So if your casting guy has a fully repeatable process...and you slice and dice one looking for holes...you are almost guaranteed future pours will come out the very same. If there is a corner or something that is cosmetically off coming out of the box, mention the broom straw to him stuck and removed to that point in the sand ...he'll giggle.

[t-time]

They are made by an industrial crankshaft manufacturer. All phases of production is done by them, casting, machining, heat treating, grinding and balancing. Since that is their business I have to put some trust in them knowing what they are doing.

[Henry K. Lee]

Mark I was even skeptic at first and did my research and it proved me wrong. Your design with "Modern" metallurgy, hardening, etc will work excellent for a much needed part! HATS OFF! Let the nayers and slayers go away..., they are not worth all the negativity. They said a 165 hp T engine was impossible..., now that I made one they want the dyno-meter sheets. I say..,"You got that kind of money"? It is done.., now some are eating crow and humble pie!

ROCK ON!

[Craig Leach]

Hi Hank,
Have you ever met Joel Young? I don't know what the last dyno was but his first was 150HP He eventually went over 200mph @ Bonneville with
a T engine in a streamliner. He drove the flathead V-8 guys nuts when he did.
Craig.

[Henry K. Lee]

Yes Craig I have but never met him. I was going to do the same thing but the So-Cal kroney club runs the show at Bonneville and "their" agenda trumps all engineering data produced. They can keep it! I am happy knowing I did it with dyno results too and they are for sale with all engine specs......., $75,000.00.

Hank

[Ken Buhler]

GO HANK!! That's awesome! Although secretly, I would like to make more power, but I don't know if I can afford it or how to do it.