They appear to be top heavy because they have a short skirt. A short skirt is generally permissable on a forged piston because of the greater strength over a cast piston, which uses a larger skirt. Wobbling? Not if the bore is correctly set up. If it starts to 'wobble" you'll hear that distinctive hollow slap noise.
As for the grooves.....yea, an air filter is good, but you must balance between your deisred airflow through that filter vs. it's filtering capabilities. A 10 micron paper filter is going to be very restrictive as opposed to a cotton gauze/mesh filter like the K&N. Keep in mind that some of those verticle grooves may have been caused by carbon particles comming loose from the combustion chamber, also. It is one of many things you will see if you have run it with a rich mixture for extended periods. Scott --- phil brookman <p...@ntlworld.com> wrote: > having just looked at these 1835 pistons they are > real top heavy > in relation to the gudgeon pin- mahle type > just wondering what the effects of this is > may not be a problem > but in a flat 4 i think it may encourage wobbling > > there does not seem to be much support from the > gudgeon pin downjust > some little tab about 40mm by 13mm which is the > widest part i think > but wear this small area and it will wobble even > more > > btw is ther anyone who has hight time engines on the > original pistons > rings and bores . > beginning to think looking at some of these vertical > lines in the > bores that an air filter might be a good thing > > view s please > phil > __________________________________ Yahoo! Mail - PC Magazine Editors' Choice 2005 http://mail.yahoo.com
