Hmm.. I don't think so. Poking with .NET Reflector into the source code of Microsoft.CSharp.CSharpCodeGenerator (System's internal), we find this:

private void GeneratePrimitiveExpressionBase(CodePrimitiveExpression e)
{
...
    else if (e.Value is string)
    {
        this.Output.Write(this.QuoteSnippetString((string) e.Value));
    }
...
}

and ... this:

private string QuoteSnippetString(string value)
{
    if (((value.Length >= 0x100) && (value.Length <= 0x5dc)) && (value.IndexOf('\0') == -1))
    {
        return this.QuoteSnippetStringVerbatimStyle(value);
    }
    return this.QuoteSnippetStringCStyle(value);
}

And if you dig further, both functions are not configurable.