5 main, chev, crankModel A engine

George Miller

George Miller

Well-known member
I know this is not for ever one, so don't look if you do not want to see a chev crank in a, A engine.

After a couple of years I'm back working on this engine. Today I started to make rods for this engine out of 7075 Alum. I made a wooden one first to make sure my math was right. If there is any interest I can post some pictures of making the rods along the way. This engine will be for my home built over head cylinder head.
 

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George Miller said:
I know this is not for ever one, so don't look if you do not want to see a chev crank in a, A engine.

After a couple of years I'm back working on this engine. Today I started to make rods for this engine out of 7075 Alum. I made a wooden one first to make sure my math was right. If there is any interest I can post some pictures of making the rods along the way. This engine will be for my home built over head cylinder head.
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Oh, Ya, George! PICTURES.

Herm.
 
Day one. The picture of putting in wrist pin holes. Also the wooden rod that I made to make sure my math was right. Also to make sure it cleared every thing in side the engine. The alum rods will be a little different in shape.
 

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Thanks for this post Mr. Miller. How about some specs on the crankshaft. Been trying for some time to find one like this. Never thought to look at chev as the source.
 
It looks like the center lines of #2 and #3 journals may be offset from the bores? I'm curious how you will handle that. Ron W
 
Miles in MN said:
What is the source of the Chev crank and cam? Are they early or are they from the 153 cid overhead? Didn't Chevrolet transition from four to six cylinder in 1927 or 28? Very interesting project!!
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They went to the 6 cylinder in 29. The crank is from a V8, so you can not use the A cam, because the A is a flat crank. The chev is 90 degree crank. The valve timing would be wrong.

The 153 crank would be great, but it is to short for the A block. The A block is wide between 2,3 cylinders because of the dist. going through the head and into the block.
 
George, I don't think you can get a "smooth" firing order using the V8 90 degree crank. Depending on how you set up the valve timing, a 720 degree firing cycle would go 180-90-180-270 or 180-270-180-90. You can't get 180 degrees of crankshaft rotation between each of the 4 cylinders in the firing cycle. Seems to me the engine would run ruff.
 
Yep, as Al said..........I wonder if it will sound like a pair of John Deere tractors running together?:confused::D

It will be interesting..........as well as a lot of work. What is the stroke?
 
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