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Engine building No Nos

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Well-Known Member
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Nov 10, 2006
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Monroe, Louisiana
Thought I would post couple of popular custom engine practices I've run across that can turn bad.

They are:

Chrome cylinder base nuts. The chrome reduces the friction between the nut and the cylinder flange resulting in over tensioning of the cylinder base stud to acquire the proper torque values. The studs can fail.

Also chrome plating of the cylinder base flange plates used on some narrow flange engines. Same result as above, worsened with the use of chrome nuts.

Powder coating of the crank case. The powder coating process requires the case be heated to 400deg.F and this can alter the properties of the alloy. The result is a case more likely to "fret" and are more prone to leaking at the seams.


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