Counter weight cranks

J

jnunez1955

Member
Hey, i found a 32 crank for sale locally for 300 bucks....but im still trying to weigh my options.

I know i want a counter balance crankshaft in my A engine.
I can either put a 32 crank, or pay 525 bucks to have my crank machined and ad counter weights to it...and im trying to figure out which one is cheaper....or an better option.

Some people told me that a 32 crank, is more likely to crack vs the Model a crankshaft....in addition, a 32 crank will required 32' connecting rods and a 32 oil pan for proper fit and oil pan clearance...is this true?
If it is...it might certainly be a better option to stick with the A crankshaft and so i wouldnt have to get a new oil pan/rods.

but, whats your opinion?
 
A 32 crank needs 32 rods to match the larger pins,1.875 vs 1.500. With the larger rods, you will need the extra clearance of the 32 pan which will have to be cut off at the back to mate with the A bellhousing.
 
I too am weighing my balanced crank options. If you really want to get nutty, check out burlingtoncrankshaft.com. Pricey, but apparently well worth it.
 
First, you can't put a B crank in an A block without some major grinding. The B mains are 2" and the A is 1.625". The bolt holes for the main bearing bolts are wider spread so the B crank is too wide for the saddles.

Second, if you change the crank, chances are you will have to put in new rods and, regrind the rod journals. You will inevitably have to regrind the mains so this means new main bearings.

Sounds like if you accomplish the mods you describe, you will have to have some deep pockets. Even if you have your crank counterweighted, you will have to have the crank ground and repour the bearings.

If you are rebuilding the motor, the counterweighted crank is a good thing and can be economical but, if you just decide to just do the crank, it could get expensive.
 
It sounds like you're sure the 32 crank has counterweights. Most 32's did not. Only those made in 33 and later.
 
James Rogers said:
First, you can't put a B crank in an A block without some major grinding. The B mains are 2" and the A is 1.625". The bolt holes for the main bearing bolts are wider spread so the B crank is too wide for the saddles.

Second, if you change the crank, chances are you will have to put in new rods and, regrind the rod journals. You will inevitably have to regrind the mains so this means new main bearings.

Sounds like if you accomplish the mods you describe, you will have to have some deep pockets. Even if you have your crank counterweighted, you will have to have the crank ground and repour the bearings.

If you are rebuilding the motor, the counterweighted crank is a good thing and can be economical but, if you just decide to just do the crank, it could get expensive.
Click to expand...


james is right.... its not just a wam bam thank you man swap. but....if you have to grind the crank to fit it into the engine than it would be a good time to offset grind it and make it a stroker 4 banger mmmmmmmm
tk
 
I also looked at the Burlington counter weighted crankshaft for my new engine, but decided to use a counter weighted "A" crank because of the added cost of having the Burlington crank cross drilled for full pressure oiling (another $250.00 added to the $995.00 for the new crank). A Schwalm's cross drilled and counter weighted "A" was cheaper then the Burlington crankshaft without the added cost of cross drilling.
 
You won't need a B pan if you use 12 point rod nuts, they are smaller in OD than stock nuts, and much stronger. I would use the so called C crank, it has counterweights and I suspect by the price that is what you are looking at? I recently put a C crank in an A block by turning the mains down half way to A size and boring the block to fit. If I were to do it again I would turn the crank to 1.800 and line bore for insert bearings, they are 2.000" OD and just clear the bolts.
 
So, this is my second evening exploring your wonderful site and I came upon this thread about counter balanced cranks. Made me think of some in my shop. I don't really know what I have and I'm willing to part with them but I need to figure out a fair price for them first. Any help educating me would be appreciated.

Here is the first one:
 

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I also have some "B" blocks...I think! This one is just a bare block. There is no ridge at the top of the cylinders. The babbitt is in great shape. I'm not sure it has ever been used. It is a "diamond" block and the diamond has a "2" struck into it. What's that all about? Value?

Thanks,

Steve
 

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I have a counterweighted "C" crank in my "A" engine. It was turned down similar to what Jim B indicated above. I used stock "B" rods for which I did put small dimples on the sides of my A oil pan for a little extra clearance. I also did install a Bill Stipe cam as suggested by Mark to finish the project. It runs great and has almost 9000 miles on it.
 
Why not just have a good A crankshaft counterweighted and use A rods ? Would save a lot of money . No pan problems, not having to worry about B rods, etc.

Ron
 
I agree with Ron you install a set of weights on an A cranks and balanced for $250 I had one done now you will ask me where? in Ontario Canada Gord. B by the Bay
 
I think a new burlington crank(spendy) would be best because the main bearings would be stock. IMHO a lot of the problems with babbit main bearings not lasting is due to too thick bearings from turned down cranks. I bought a burlington but am in the process now of installing it along with a 39 trans and a Mitchell OD.
 
Another option:
SCAT now markets a forged, counterweighted crankshaft for the A engine. It is available both standard and drilled for pressure. Available through Summit Racing as well as other suppliers.

Ken
 
Over the years we have used all the various options to obtain the counter balanced crank. We sure like the Burlington Crank that is brand new, with the counterweights manufactured as part of the design. I think they are still around $900 but there is nothing else to do but put it in. And it fits the Model A block with out any modifications. We actually have two of these in engines, one in a Babbitt engine that has about 15,000 miles and running well the other in an inserted engine and it is doing great, matter of fact an article about that engine will be in the next Model A Times due out in January.
 
One little "clinker" that many people do not think about when installing a CW crankshaft onto babbitted bearings. :confused: Do you know how you remove the rear main cap to adjust the babbitt clearance when there is a counterweight in the way?? :eek:

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