Mark and All: Most, if not all "B" engines (not rams and hemis) utilized an insulation between the valley cover and the intake manifold. It is made of aluminum foil with fiberglass inside. I made one up myself for the 300H, before I was aware a friend of mine here in Tallahassee has been producing them for years. It may be of help, at least Chrysler thought it necessary----whether for heat or sound, or both, I don't know. Link to the insulation on Dave's web site is: _http://www.performancecargraphics.com/Manifold_Insulation.htm_ (http://www.performancecargraphics.com/Manifold_Insulation.htm) Hope it helps. 300ly, Gil C. In a message dated 9/9/2009 10:55:55 A.M. Eastern Daylight Time, mplindahl@xxxxxxxxxxxxx writes: Hi All, I have tried a few things to reduce/eliminate the boiling of gas in the carb bowls after hot weather driving and shut down of 383. Within a few minutes, the carb gets so hot that the fuel is boiling and flooding occurs. I have seen it a few times. The engine does not run hot during normal driving. Temp/Gas Guage seem to be calibrated with temp guage around the 1/2-3/4 mark. At idle and normal driving speeds, the engine runs strong. Newer open chamber heads were installed about 18 months ago along with hardened seats for unleaded gas. I reinstalled the original valley pan and now have a 4 bbl. carb instead of the original 2 bbl. Here is what I have tried. Installed gasket between hood and radiator support: It looks good, but does not help my problem. Installed new needle/seat in carb: Flooding still occurs, but somewhat less. Waiting for stainless steel plate to install under carb to reduce heat transfer: will advise. I have removed the spring from the exhaust manifold allowing for free movement of the valve: no change. I took off the heavy metal air cleaner top and now have the air filter exposed using just a flat top: no change. I also vaguely remember that some valley pans have the the heat passages blocked off to not allow heat back up to the carb. Since I don't drive the 300 in the winter or much when it is cold, is this a good idea? Are there certain valley pans with the heat passages cut out and some with them blocked off? Any ideas would be helpful. Regards, Mark Lindahl '63 300 Conv. [Non-text portions of this message have been removed] ------------------------------------ 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 For archives go to http://www.forwardlook.net/300-archive/Yahoo! Groups Links [Non-text portions of this message have been removed] ------------------------------------ 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 For archives go to http://www.forwardlook.net/300-archive/Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Chrysler300/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/Chrysler300/join (Yahoo! ID required) <*> To change settings via email: mailto:Chrysler300-digest@xxxxxxxxxxxxxxx mailto:Chrysler300-fullfeatured@xxxxxxxxxxxxxxx <*> 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/