Wow, just read Tech Topics in the new (Feb 2010) MoPar Action and your question was partially answered very well + more. Basically get rid of full shrouds and replace with a Stock Viper (Late) or a 98 Grand Cherokee 360 shroud & fan assembly. It states they have serious fans and vent flaps for high speed driving. The owner says it fixed his heating problems & it took .26 off his ET? The article also goes onto diagnose a problem with pressure in the system caused by galvanic corrosion 3 days after the engine has cooled down. Herb 1956 Plymouth Belvedere 361 1959 Coronet 326 Poly 1963 Fury 2D/HT 6.1 1963 Sport Fury Convertible 361 1970 Challenger RT 440 - 4 Sale 1999 Durango SLT 5.9 2008 SRT-8 Magnum 6.1 St. Louis, MO. http://1962to1965mopar.ornocar.com/mmo42009.html -------Original Message------- From: Gary Pavlovich Date: 10/24/2009 11:30:54 PM To: 1962to1965mopars@xxxxxxxxxx Subject: Polling on your best cooling experience; OEM copper radiators and clutch-fans vs Just checking with the group to see if the touted aluminum radiators (single or double pass) and with or without electric fans & shroud do a better job of cooling a High Performance Mopar engine (400-500HP) better than our good old 3 core (or four core?) High Efficiency copper radiators w/shrouds and Mopar clutch-fans? Please reply via private or list-wide e-mail if you feel it factually beneficial to the group as well. Thank you in anticipation of the empirical data and personal experience vs. the "marketing blurbs" of the catalogs, radiator/fan companies, and hear-say." Gary Pavlovich [Non-text portions of this message have been removed] ---- Please address private mail -- mail of interest to only one person -- directly to that person. I.e., send parts/car transactions and negotiations as well as other personal messages only to the intended recipient, not to the Clubhouse public address. This practice will protect your privacy, reduce the total volume of mail and fine tune the content signal to Mopar topic. Thanks! '62 to '65 Mopar Clubhouse Discussion Guidelines: http://www.1962to1965mopar.ornocar.org/mletiq.html. [Non-text portions of this message have been removed] ---- Please address private mail -- mail of interest to only one person -- directly to that person. I.e., send parts/car transactions and negotiations as well as other personal messages only to the intended recipient, not to the Clubhouse public address. This practice will protect your privacy, reduce the total volume of mail and fine tune the content signal to Mopar topic. Thanks! '62 to '65 Mopar Clubhouse Discussion Guidelines: http://www.1962to1965mopar.ornocar.org/mletiq.html. This email was sent to: arc.6265@xxxxxxxxxxxxxx u/?bUrDWg.bSONJP.YXJjLjYy ?p=TEXFOOTER