Well, I have a different opinion than Sam on this Sandcast pairing. As well.
Studying Sandcast engine top crankcase casting dates:
From June 2, 1969 through June 24, in a period of 22 days, 1,358 engines were cast, averaging 62 engines per day over this time period.
I believe June was the highest month of Sandcast engine production for these special engines.
If Honda produced 62 engines a day as the daily average for the period of April through September 1969, there would have been around 11,000 engines total cast. We know that only 7,414 were stamped, some scrapped, some used as replacements, but total production not this high.
Our VIN directory contains very few top engine casting dates, but the data I used to pull this information was from the directory. E2241 top casting date is 6-2 and E3599 is 6-24 a difference of 1,358. Lots of missing top casting dates, but I know for a fact other engines have June casting dates that fall outside this range. E1685 as an example has a 6-23 top casting date.
Something happened in the E31XX range as very few of these engine show up. 3088 would have likely/probably should have an E31XX number give or take.
In our directory 3043 is paired with 2765 with 6-13 cast date, 3045 is paired with E2718 with 6-11 cast date.
On eBay 3088 is paired with E2414, I believe this sure could be a factory paired engine, as June produced high numbers of engines., in fact probably more engines than frames, but we will never know, just an opinion.
We continue to learn more as data surfaces, fact is, we need more Sandcast owners to update their top crankcase casting dates to better understand these pairing.
Best,
DW
