Yeah, Windsor blocks were 2 at a time too....so @my68barracuda do the suffix numbers mean ANYTHING as related to quality? That's the base of my theory. It sounds like a -1 and a -8 (-15) are going to be dimensionally the same? So this last number is meaningless in regards to block worth...? I think so. I posted 2 340s made 1 day apart and the latter one had a lower number. Thanks for your input!
Concerning how two 340 blocks made a day apart with the latter having a lower number. The mold sets 1 & 2 and 3 & 4 could both be ran the same day. Perhaps they started running 3 & 4 in the morning, but a problem developed during the run so that pattern set was taken out and patterns 1 & 2 were set in. To keep productivity high, pattern changes could made in the matter of minutes. Basically any pattern set that was available could have been ran on any day.
Concerning pattern numbers and dimensional quality. Whether it is pattern 1 or pattern 26, typically the quality level will be very similar. Foundry tooling is typically very expensive, to maintain the interchangeability of that tooling, it usually is all made the same way.
Changes in tooling singificant enough to impact casting quality are typically introduced at the same time part design changes are introduced. Then the part number also changes. Again using slant six heads as an example. Drool tube heads have a part number, peanut heads have a different part number, hydraulic heads have a different part number. These three heads each have different foundry core processes, but are basically interchangeable and each set has their own part number.
