Is there a reasonably accurate way to measure the stroke of a crankshaft with it out of the block and no rods attached? Thanks, Rex
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Re: Crankshaft stroke
Measure the distance between inside tangents of two 180 degree opposing journals and add the journal diameter.
Or, measure the outside tangent distance and subtract the journal diameter.
Duke -
Re: Crankshaft stroke
OK, by my ciphering, it looks like 4 inches. Crank is supposed to be a special aftermarket crank for a Can Am aluminum ZL-1 engine, but no markings other than K97 2-380 ink stamped on the front counterweight. Clem said it might be a Kellogg crank, but after I spoke with someone at Kellog and sent photos, they said it wasn't theirs. They actually said it looked like a cast crank, but they couldn't tell me how to properly ID a cast vs forged crank. Just trying to identify what I've got hold of.
Thanks Duke.
RexComment
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Re: Crankshaft stroke
IIRC the 465, 494, and 510 CID Can-Am engine configurations had a 4" stroke.
DukeComment
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Re: Crankshaft stroke
The block has the 4.40 liners in it. I have spoken with 2 guys who were directly involved with the Can Am cars and engine development in the late 60s and, based on my description of the block to them, both have confirmed that I have one of a limited number of aluminum Can Am blocks. One guy said maybe 20 were made, but that seems like a low number for Can Am racing.Comment
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Re: Crankshaft stroke
Does the block have what appears to be a GM casting number or any other identifying data?
A 4.40 x 4.00 configuration rounds to 487 CID, which was not a Can-Am configuration that I recall.
The first aluminum big blocks raced in '68 were production bore and stroke for 427 CID. Then it went to 465, 494, and finally the 4.5" bore 510 CID Reynolds 390 with no liners.
There was also a short-lived "short stroke" 430 CID configuration that used a shorter than 3.76" stroke and a larger bore, but I don't recall the exact bore and stroke dimensions.
DukeComment
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Re: Crankshaft stroke
Casting number is 0-321270 and casting date is Feb 1968. No winters snowflake. Block has no provision for a mechanical fuel pump. All freeze plugs are aluminum welded in. Lifter bores are brass sleeved. Block was purchased from Smokey Yunick's auction some 20 years ago. It has a,most new Ross flat top pistons and Carrillo rods. I am planning to put it together with a set of 842 closed chamber heads (if I can find a nice set that haven't been messed with) and some type of streetable cam and put it in my 68 Corvette Sebring replica race / street car. I'm trying to document the block and its relevant history as much as possible.Comment
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Re: Crankshaft stroke
"0-..." is a prototype part number. No Winters snowflake? Maybe Joe knows who cast them - possibly and experiemental Tonawanda casting since they were gearing up for Vega block production or maybe even Reynolds.
It's tough to beat the OE SHP mechanical lifter cam for a high performance road engine that idles reasonably and makes decent low end torque, especially if the heads are massaged with 1.88" exhaust valves, which the 842s should have. You want to get an E/I flow ratio of about 0.75.
And aluminum heads are a WHOLE lot easier to grind than cast iron.
DukeComment
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Re: Crankshaft stroke
The retired GM engineer I spoke with was directly involved with the Can Am engines and worked with Smokey on designs. He confirmed that the block is genuine. We did not discuss the lack of the Winters snowflake. These prototype and experimental blocks may very well have been cast internally or in a special mold at Winters that did not have the identification mark. Anyway, it's a real neat piece that hasn't been monkeyed with too much. Not sure about the brass sleeves in the lifter bores. Someone said that sounds like a Smokey Yunick trick. Guess we'll never know now.Comment
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Re: Crankshaft stroke
Duke-----
I'd say it was definitely an "experimental" or "prototype" piece. Winters did cast many of these parts that were aluminum, although I don't know if they put their logo on them. However, parts like these could well have been cast by even smaller, specialized, "small lot" type foundries.
I don't think that any aluminum castings were ever produced at Tonawanda. When the foundry there was operating (i.e. prior to 1984), I believe they did cast iron work only. I believe that Vega blocks were produced at the GM foundry at Massena, NY, although machining and assembly was done at the Tonawanda engine plant. I doubt that Massena did these prototype big blocks, though. Generally, GM foundries are not set up for "short lot" type work.
GM used to have 2 aluminum foundries and now they have 3. The original two were Massena, NY and Bedford, IN. I believe that Massena did the Vega blocks and, possibly, the Corvair engine components. I don't know what else they did there in the past. Currently, I think they do many of the components for the inline 4, 5, and 6 cylinder truck engines.
Bedford, IN does a lot of high volume aluminum components like pistons. They also did the later LT-5 blocks.
GM's newest aluminum foundry is only new as an aluminum foundry. It's the original Saginaw gray iron foundry of old where most Corvette small block cast iron components were cast right up through the 1996 model year.
GM only has 2 cast iron foundries left---both are in Defiance, OH. One is a gray iron foundry and the other nodular iron----side-by-side.In Appreciation of John HinckleyComment
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bore was 4.44 not 4.40 *NM*
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Re: bore was 4.44 not 4.40
Mark and Duke-----
Yes, the aluminum "Can Am" big block engines which used cylinder liners did have a bore of 4.440". The "short stroke" 430 cid engine had a special 3.47" stroke crankshaft. The 465 cid version used the same crankshaft stroke as 396/427----3.76". The 495 cid version used the same crankshaft stroke as 454----4.00".In Appreciation of John HinckleyComment
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Re: Crankshaft stroke
Joe -
As I recall, the Reynolds aluminum production plant (that normally produced aluminum ingots) was about six miles from the Chevrolet Massena foundry in the Corvair/Vega days, and a fleet of insulated trailers hauled molten aluminum from Reynolds to Massena and poured it directly into the Massena holding furnaces. Don't know how long they did that, but it was a big deal at the time.Comment
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Re: Crankshaft stroke
Wow, did they need special permits to do that? I can just imagine what a wreck would do spilling molten aluminum?
...wonder if it could still be done today?
DukeComment
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