Will cleaning the valves improve performance? Yes.

Will you feel the difference? It really depends on the present state of the valves but the answer is probably "no".

Is it worth going them while one's in there? That really depends on the end objective and the availability of resources like time and tools.

Just to give an idea of the worth involved, here is a Jafro video which shows how to remove the valves and valve springs from a 4G63 cylinder head.

Here is another one detailing how he cleans the valves and seats.

Should I lap my valves if I have easy access?
I'm using x64 Ubuntu. A few months ago I accidentally messed up the groups/owners of all files on /, but managed to fix it using a VirtualBox install of Ubuntu.

Now I'm running into a problem that I think is related to that mistake. When I try to reinstall ia32-libs (Skype is having problems so I need to reinstall those libs) I get an error message:


  /var/lib/dpkg/info/ia32-libs.postinst: 40: /usr/lib32/gdk-pixbuf-2.0/gdk-pixbuf-query-loaders: Permission denied


ls -al /usr/lib32/gdk-pixbuf-2.0/` is this:

total 476
drwxr-xr-x  3 root root   4096 2011-09-24 17:08 .
drwxr-xr-x 53 root root 143360 2011-09-24 17:08 ..
drwxr-xr-x  3 root root     40 2011-09-24 04:44 2.10.0
-rwxr-xr-x  1 root root   9648 2011-04-05 00:40 gdk-pixbuf-query-loaders


I have tried to reinstall gdk-pixbuff-2.0, but it didn't work. How can I fix this?
