HiPo Crankshaft

  • I was reviewing threads about the 289 HiPo crankshaft. Some information was quoted from my list of changes which I maintain at my website (http://www.fordsmallblock.com). From my reading, I can see the conversations were lively. At the risk of flaring up emotions, I thought I would share a more indepth comment on my source at the foundry.


    He was an engineer. His initials were B.H. He was not some person I heard about. He stopped by my booth at a Columbus, Ohio, swap meet and introduced himself. He gave me information he could not have known outside of Ford. By that I mean his explanations matched what I had observed, but had not reported in my book. Specifically, he was telling me that the info I had printed in my book on HiPo crankshaft hardness testing was not correct. The information I had printed was from people insisting that there were hardness marking on the crankshafts. He said he was not intimate with every detail of HiPo production, but he was in and out of the foundry at the time. So his comments were his recollections. I found no documents to help verify his account. But, they did seem to match the evidence.


    His recollection was that when the HiPo cranks were to be poured, the foundry people added a couple shovel fulls of nickel and manganese to the molten metal. As he recalled, it was not a very "scientific" method -- just "some" to add to the strength of the metal. He said the same molds were used for both standard and HiPo castings. He further said that the polished area on the crank was done so that they could "see" the grain boundaries under a microscope -- actually, more like a super magnifier (not like a lab microscope). He also could not recall the grain-count that had to be achieved in the inspection -- just some number had to be equalled or exceeded.


    Before I knew any of this, I looked all over my crank (from a K-code 63 Fairlane that had never had the engine apart) for the hardness test I was told would be there. I couldn't find it. Currently I have a second crank from a HiPo engine and it did not have any hardness marks either. But both had the polished area on the rear counterweight. I have seen a few other HiPo cranks from engines I knew were original and they had the same characteristics as mine. I can't speak for other HiPo cranks.


    The engineering drawing show two differences between standard (C3AE-6303-N) and HiPo cranks (C3OE-6303-C). One is the material. Standard cranks call for Nodular Iron ESE-M1A147-A. The HiPo calls for Nodular Iron ESE M1A172-A. The other difference was in machining. The journal radii spec tolerances were tighter and the #3 bearing thrust surfaces had a finer micro finish -- in short, the machining was more precise.


    I did find it interesting that when Ford came out with the C8OE-6303-A 302 crank for 1968, the material was Nodular Iron ESE M1A172-A -- same as the 289 HiPo.


    I know the discussion of HiPo crankshafts will go on as I cannot provide documents. It is "recall" evidence and info from people who were able to view Ford sources. But, it all fits with the evidence of 1M markings on both standard and HiPo cranks, the polished area, lack of hardness markings in this area, and difference material specifications. In summary, the HiPo cranks were made using standard molds but with a different metal content. The rear counterweight was polished for microscope inspection for grain count and machined with closer precision in the journal radii and thrust surface finish, then marked with orange paint. Service replacements were boxed with a unique C3OZ-6303-B part number.


    Edited by - bobmannel on 06/06/2007 21:21:19

  • Bob,


    First off - THANKS for the continued dedication to seeking the truth and sharing it with everyone on the small block Ford!


    Just to add to the pile of data - I can't say my HiPo has never been apart - In fact I'm 99% sure it has because it has the lower compression regular 289 pistons - but they measure standard. Other than that it is all HiPo. I've only had the car since 1979 - so there were 14 years of "who knows" early in it's life.


    Engine build date is mid March '65 and all my casting numbers are within days of each other in March.


    My crank may have a polish mark - may not - the area is so small it is hard to say for sure. I CAN say for sure that it has a hardness mark as shown in your book - 57 in a triangle - JUST like your picture and in the exact same place.


    I think we have all said it is possible that some parts were actually checked and stamped to confirm the "batch" was up to spec. Could it be possible that while this engineer was able to see the "production" process, he wasn't exposed to the Quality Control steps? Maybe - and maybe this is where the hardness stamps come into the equation - with the remainder of the cranks just getting a "visual" inspection. This would make sense with industrial standard QC audit processes.


    Just my 2 cents!


    Thanks again for the "sharing the wealth" of information - your book is a GREAT reference source.

  • The two marks (triangles with 42 and 65) shown in my book were off standard crankshafts. I still don't know their meaning or if they are hardness tests.


    I did come across a prototype 289 HiPo and each of the main bearing caps were hardness tested in two places.


    [Blocked Image: http://www.fordsmallblock.com/Pictures/HPmaincapc.jpg]


    The Brinell hardness test uses a 10mm ball as an indenter. These are too small for that, so I suspect it was a Rockwell hardness test. If the crankshaft was checked with a hardness test, there has to be an indenter mark somewhere on the crankshaft. If it was not in the polished area, then there is no need for the polished area. And if it was in the polished area, I sure can't find it.

  • Bob,


    My experience is the same as yours. I have a 65 VIN stamped block and trans that were original to the car. When I disassembled the motor the 1M mark, the polished counterweight, and the orange paint were all present. The crank had yet to be turned and was standard size on both the rods and mains. (This is the motor I sent you photos of during our correspondence.)


    Edited by - round2K on 06/08/2007 02:41:46

  • I have an Aug. 65 date dated engine that was std bore and appeared to be never taken apart when I found it. The polished area was on the rear counter weight, and there were 3 random "K" stamps over towards the other side of the weight. Anybody ever seen this?

  • "K" stamps over towards the other side of the weight.


    Could that stamping be an "H" instead of a "K"?


    Edited by - kar-nut on 06/09/2007 08:08:47

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