Hola MoPar has been producing the big block and raised big block since 1958 and 1959. From the beginning until even now they have had many many years to figure our how to make the most of their power plants. The raised block version had the 413 cubed engine in Imperials from 1959 until 1965. Starting in 1966 the 413 became the 440 as we know. The 1967 Imperial's weight was lower than the 1966 year. As we also know the 413 and 440 was used in vehicles that weigh less than any stripped version of the 59 to 66 Imperial. What this means is the cams that work in a lighter vehicle do not work correctly in a heavy vehicle as the framed Imperials. That is why I said to Marty of which type or style of cam to use, the now called RV spec'd version. The 1966 Imperial had a intake duration of 252 and the exhaust duration was 260 degrees. The intake valves had a lift of 0.425" and the exhaust valves were 0.435". In 1967 the spec's for the lighter Imperial had been raised to 256/260 duration and the same lift for the regular engine and 268/284 and a lift of 0.450"/0.458" for what they called the power pack engine. To translate this to todays lanuage means the MoPar Cam # P4286675 ( 260/260 degrees duration and a lift of 0.430/ 0.430 ) , which is slighty "better" than 1966's cam or # P 4452783 ( 268/284 duration and the lift is 0.450/ 0.458" ) for the 1967 power pack cam. To me, the cams or whatever of other companies have is just a copy of what MoPar has been doing since 1959 in our RB's . The porting template is # P 4120437 ( if you want this, just email me ... not the club ). There is a infamous MoPar HP exhaust manifold for the framed 1959 to 1966 Imperials. This exhaust manifold is a bolt on/in that does not need a five lb. hammer or the such. If you have this year of car, please look at this ( http://www.1aauto.com/1A/ExhaustManifolds/Dodge/PickupFullSize/PLP1390041/67559 ). Uncle Rodger & Aunt Gabby Colo Spgs ----------------- http://www.imperialclub.com ----------------- This message was sent to you by the Imperial Mailing List. Please reply to mailing-list@xxxxxxxxxxxxxxxx and your response will be shared with everyone. Private messages (and attachments) for the Administrators should be sent to webmaster@xxxxxxxxxxxxxxxx To UN-SUBSCRIBE, go to http://imperialclub.com/unsubscribe.htm