Forged pistons

[George Roffe]

Jay Stewart wrote:

> > Coatings work and for internal coating Swain's work the best.

>I have done a lot of research over the past few days about this.

> >From what I have found and seen, this may not be the case in a street
> motor.  The barrier coatings do the wrong thing, they prevent the head,
> pistons, etc from soaking up the heat like they should, and getting it
> out of the combustion chamber. Results range from hotter EGT's, to less
> total timing advance being available.

>In a racing application where you have more than enough octane of known
>quality I can see it. But on a street motor?

This is exactly the point.  You *don't* want the head, pistons, etc. to
soak up the head.  You want the higher EGT.  This is more energy in the
combustion process/exhaust rather than lost into the block/head, etc.  This
would not lead to less total timing being available because the coatings
*lessen* the chance of detonation and pre-ignition.

I think whoever is giving you the information is deciding the answer first
and altering the interpretation to try to support the pre-conceived
conclusion.  It just boggles my mind that someone would suggest that you
actually want the combustion chamber to soak up heat.  The opposite it true
in reality.

George Roffe
91 SE-R
00 328i
84 944 race car under construction