On Wed, 08 Sep 2004 12:49:14 -0400, Corky Scott
wrote:

On 07 Sep 2004 20:39:22 -0700, Bob Fry
wrote:

"It is an excellent additive for auto conversions, where it reduces
buildup on oxygen sensors and plugs. If you have to use 100LL, then
this stuff is for you. Prevents valve seat erosion from valve seat
micro welding. It is equivalent to TCP.

I am not a internal engine combustion expert, and don't play one on
TV, but I have a couple of thoughts to add regarding this statement:

The auto conversions I'm aware of tend to run cleaner than certified
aircraft engines regardless whether they are carburated or fuel
injected. This is because they normally run with a mixture closer to
the stochiometric ideal than do the aircraft engines during the
settings other than leaned for cruise.

Most auto engine conversions do not have fixed timing...
[SNIP]

With all this in mind, the auto conversions tend to run leaner
mixtures most of the time which ,(this is where opinion raises it's
head) should reduce lead buildup in auto conversions. Why? Because
the nearly ideal mixture ratio results in near complete combustion.

Corky, do the computers that adjust the timing use the O2 sensors in the
exhaust? If so, they're probably getting hosed up when leaded fuel is
used. But if you're *not* using 100LL, you don't *need* TCP....

Ron Wanttaja