Is he using Premium gas?  The higher compression GW engines call for premium gasoline.

Allan
--
1991 Vanagon GL

On Tue, 15 Sep 2009 23:04 -0400, "Ian Allan" <ian.allan@BMTS.COM> wrote:
> I have a friend who purchased a van with a Go Westy 2.4 engine. The
> engine has suffered from detonation issues among other things. Any
> ideas as to practical machining processes to REDUCE the compression
> ratio?
>
> Ian