Brandt: Combustion technology always involves the tradeoffs between material endurance, power output, economy and emissions. Current engine technology can include variable valve timing, individual cylinder spark timing control, imdividual cylinder fuel-air ratio management, variable length intake passages & etc.--all designed to enable an engine to run reliably closer to the ragged edge of failure and comply with emissions rules. Our wonderful old carbureted engines with crude vacuum and mechanical ignition timing control cannot continuously and reliably run that close to failure. You are right--you can't have max power and max reliability with our older engines as equipped in the 50's and 60's. Optimizing what you have by tuning the ignition system and carburetion is all you can do short of the old hot rod tricks of porting and relieving. Find a point you are comfortable with and enjoy the ride. Best wishes in finding and enjoying that point. BTW, I recently saw an old ad that was selling oxygen to be used as a carbon remover. Connect the oxygen to the manifold, open it up and burn out all excess carbon in a few seconds. That was a new one for me. Obviously, the point is to burn the carbon, not the pistons, valves, cylinder walls, rings, heads and plugs. I do recall advocates of water injection with the hope that the steam formed would blast out the carbon. Water injection was successfully used to cool the combustion chambers of piston-driven airplanes during takeoff and (perhaps) maximum combat power situations. Asking an engine to perform well all the way from sea level to 40,000 feet was asking a lot, even with superchargers. Our cars are pretty much limited to Death Valley (-282') to Mt. Evans, CO (14,130') C-300'ly, Rich Barber Brentwood, CA 1955 C-300 Brandt Jimerson wrote: >Hello everyone! First off, I want to convey that I understand about carbon build up (causing more pre-detonation). Secondly, I like to 'play around' with the timing at times and I guess I shouldn't mess with it especially after Jeff Carter adjusts it!! However, I found the 'max power' point with what I ended up with adjustmentwise. I basically have it back right where Jeff had it before. Anyway, here's the story: WITHOUT advancing the timing, I've been using tankfuls consisting of 1 part of leaded 111 octane racing fuel to 3 parts 91 unleaded fuel ( 91 highest in California except for a 'special' place that I go to). Lately, when stepping on it, I've noticed very slight pinging so I got some techron by Chevron to clean out the combustion chambers. So far I have treated almost 2 (two) tankfuls and NOT ONLY did I do that, but I 'strenghened the concoction' to 1 part of 111 racing to not 3, but only 2 and 1/2 parts of reg. 91, and when stepping on it, the PINGING IS EVEN WORSE.... > > ------------------------ Yahoo! Groups Sponsor --------------------~--> Get fast access to your favorite Yahoo! Groups. Make Yahoo! your home page http://us.click.yahoo.com/dpRU5A/wUILAA/yQLSAA/8LmulB/TM --------------------------------------------------------------------~-> To send a message to this group, send an email to: Chrysler300@xxxxxxxxxxxxxxx For list server instructions, go to http://www.chrysler300club.com/yahoolist/inst.htm Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Chrysler300/ <*> To unsubscribe from this group, send an email to: Chrysler300-unsubscribe@xxxxxxxxxxxxxxx <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/