So what does that give me for displacement and what does this give me for cam options? I did double check the 4-3/4 stroke as well. Ill have to get a closer picture of the springs.
STD Shovelhead cam help
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Sifton 3030 spring set with their black top collars to match the cam would be my guess. Could be S&S.
Yes, TRW 2800 or 2900 pistons made for S&S. One of the best forged pistons for shovels ever made. Those pistons will yield a listed 9.0:1 compression ratio with the 4 3/4 stroke. You can bet it might be a tenth or two lower, depending on how much the valves are sunk, affecting the volume of the combustion chamber.
Given that, the cam you had was WAY more than needed, giving a soft bottom end in exchange for horsepower in a range of rpm beyond normal operation.
I'm interested to see what Drag's wizard box says about a cam choice. My AccelPro didn't work with my new computer fifteen years ago, so I quit using it.
I would choose a cam that closes the intake valve at around 50 degrees ABDC, at .050/.053 lift timing.
JimLast edited by JBinNC; 03-26-2020, 5:40 AM.Comment
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Interested to see what you come up with! I was glad to not see any scoring in the cylinders, everything seems good in the top end. At least with the front cylinder. So with these 3-7/16 jugs, do I need a special head gasket? By the way this will be going in a kick only street bike if that makes a difference for cam choice.Comment
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Given that those motors are hard on rings, I would rering it since you are this far down. Long stroke, short skirt, and loose clearance means shorter ring life. Standard shovel rings will fit those pistons.
You can use a standard shovel head gasket, but use a good one, no blue Teflon gaskets!
JimComment
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So was I ....
This is with the 105 cam ...
On the head gasket choice ... Hard to beat James Fire Ring ...
If you're up for a little work you could machine a .004 step on the gasket surface of the jugs... That allows for a bit more crush on the metal fire ring ... (Poor Boys O-Ringing, per say)
All of S&S cylinders has that step for the Shovels. ..
Last edited by Dragstews; 03-26-2020, 6:25 AM.Take my 45 and outrun em all ..Comment
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All of these cam specs are very new to me and rather than guessing and making a mistake, do you have any suggestions for a cam that fit in the "Choose a cam that closes the intake valve at around 50 degrees ABDC, at .050/.053 lift timing" catagory? From that last picture it looks like the L5 is off the table without head work, what about the #7?Comment
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Yes ....
How many miles do you think that motor has on it since it's been built ... ??
BTW ....
That No.7 cam has a .510" valve lift ....
Your Sifton 105 has .475" ...
Look up Leineweber J-2 ...
That may be a plug & play cam with what you got going on with your springs ...Last edited by Dragstews; 03-26-2020, 7:24 AM.Take my 45 and outrun em all ..Comment
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