[TechGuy]

Orban,

Thanks for the quick reply. I'm not sure what you mean by check for the variable and force the thread index.

The search_sphinx.php has the following code which appears to check for replyless:
if ($vbulletin->GPC['titleonly'] and ($vbulletin->GPC['replyless'] OR $vbulletin->GPC['replylimit'] > 0))

if ($vbulletin->GPC['replyless'] == 1)
$cl->SetFilterRange('replycount', 0, $vbulletin->GPC['replylimit']);
else
$cl->SetFilterRange('replycount', $vbulletin->GPC['replylimit'], 9999999999);

And replycount is in the postsrc in sphinx.conf