I am posting this email for David, as it got misdirected. Another Mopar mystery. My recall is that there is no definitive reference for the meaning of Mopar engine casting numbers like AAQA on some of the blocks, like what Darrell Davis' reference books did for 1960 to 1965 Dodge and Plymouth hi-po cars. There was speculation that AAQA meant the casting was made to use Ambient Air Quality Analysis to see if the casting process met The Clean Air Act's monitoring requirements for pollutants. As for 2R or 3R, I've not seen any explanation as to what they mean. Thanks, Gary H. > -------Original Message------- > After I removed the power steering unit from my 1962 Dodge, to have it rebuilt, today I cleaned the area of the block behind it. > > I found AAQA 3R stamped on the block that I had not seen before. > > It appears that the casting remarks AAQA are on all max wedge blocks. > > I have been told that sometimes the 2R is a 3R and most are 2R. I don’t know what the differences are between the 2R and the 3R. > > Several years ago the entire engine was sent to Ray Barton Racing Engines to be rebuilt and given some upgrades. It was sent off as a 413 Cross Ram and came back bored out to a 426. > > I never paid attention to the AAQR casting and do not recall seeing thar 3R mark at the time, before or after > > Anyone of care to give a thought on what the differences might be between a 2R and 3R casting mark? > > Thank you, > > David C Hurd > > -- -- -- Please address private email -- email of interest to only one person -- directly to that person. That is, email your parts/car transactions and negotiations, as well as other personal messages, only to the intended recipient. Do not just press "reply" and send your email to everyone using the general '62-'65 Clubhouse public email address. This practice will protect your privacy, reduce the total volume of mail and fine-tune the content signal to Mopar topic. Thanks! 1962 to 1965 Mopar Clubhouse Discussion Guidelines: http://www.1962to1965mopar.ornocar.org/mletiq.html and http://www.1962to1965mopar.ornocar.com/general_disclaimer.html. -- You received this message because you are subscribed to the Google Groups "The 1962 to 1965 Mopar Mail List Clubhouse" group. http://groups.google.com/group/1962to1965mopars?hl=en. --- You received this message because you are subscribed to the Google Groups "The 1962 to 1965 Mopar Mail List Clubhouse" group. To unsubscribe from this group and stop receiving emails from it, send an email to 1962to1965mopars+unsubscribe@xxxxxxxxxxxxxxxx. To view this discussion on the web visit https://groups.google.com/d/msgid/1962to1965mopars/20231009141735.58525.qmail%40server309.com.