it's 6 x 1.0 metric thread. - those little studs on top of the 1.9 intake
runners.
what your common "10 mm hex wrench size"  nut goes on.

----- Original Message -----
From: "David Beierl" <dbeierl@ATTGLOBAL.NET>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Monday, August 04, 2008 3:09 PM
Subject: Re: ECU optimization -- one quick question

> At 05:45 PM 8/4/2008 -0400, David Beierl wrote:
>>coolant crossover pipe is bolted to a little M6 stud rising from the
>
> Not even M6...M4, maybe.  Senior moment.
>
>
> --
> David Beierl - Providence RI USA -- http://pws.prserv.net/synergy/Vanagon/
> '84 Westy "Dutiful Passage," '85 GL "Poor Relation"