I have seen these on a few engines, including my Bumblebee....never come across any reference that says what they indicate.

Any ideas? Dave P? Steve G? Paul H? Perry?

This engine is allegedly from a 75 2.0L

DBR.

925 Days Before Rust.

September 2, 1975 production run. <_<

Do I win a prize?

And my final answer is.............,

I've seen a lot of those #'s, but they were always on the inside. Those are 75/76 exchangers.

My '75 has "924" on them. I've wondered this also.

No, I don't know the answer.

My Sahara Beige engine tin has 621 on it. My car was made in July 1973 so that kind of blows any theory that the last number represents the year.

Maybe if we get enough people to reply with their 3 digit number along with their year and engine, we may be able to fiigure it out.

example (621 - '73 2 Liter)

Is the middle number always a 2 ? Mybe the 2 means 2 liter.

We need more data to figure this out.

621 on mine. It's out of a 73 2L.

the 75' 1.8 has 918
EA381

kevin

I also have wondered about them. We do need more data. There does seem to be an ascending sequence over the years at least.

There is also a label on the transmission bellhousing, but mine are too far gone to see anything.

I can try to collect and analyze the data.

DaveP