DerbyDad03 wrote:
....

The project I need these bolts for has some very strict rules about
manufacturing your own parts or modifying readily available parts. My
options for this bolt are pretty limited - carriage or elevator, by
rule. Due to air-flow issues over the surface where the bolts will be
installed, the carriage bolts would be a distant second choice.

These bolts are for a Soap Box Derby car ...

I have hard time believing there's high enough speeds involved the drag
differential would show up...

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