He's right concerning the "Chlorine based" additives. When we were racing Toyota's the owner was using a "power adder" http://www.hotrod.com/techarticles/nitropropane_power_adder_additive/index.h tml The more of this stuff you add the faster you go until,,,, he was adding SO much it was washing down the cylinder walls and started galling pistons. We contacted a company called ProBlend http://www.pro-blend.com/products.htm While their engine additive DID stop the piston galling it introduced another problem. The first teardown after using problend showed a considerable amount of rod bearing flaking which we had not had before. We never suffered a failure but had to reduce the amount of run time on the motors to facilitate rod bearing replacement. And remember using ZDDP additives in any engine using o2 sensors is asking for reduced life due to the phosphorus coating the sensor. Over time the sensor becomes "lazy" and gives incorrect readings. Since most late model engines are now "rollers" it's not helpful for them. In engines using "flat tappet" type followers and high spring pressures it's almost a must! Shell Rotella-T has been one of the few to still have ZDDP but not ALL the weights do. If it has a "approved" starburst on the label it's a reduced ZDDP formula. Bruce Hevner -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://list.amc-list.com/pipermail/amc-list-amc-list.com/attachments/20090614/0bfc83ef/attachment.htm> _______________________________________________ AMC-list mailing list AMC-list@xxxxxxxxxxxx http://list.amc-list.com/listinfo.cgi/amc-list-amc-list.com