I've got a 70 chevelle 396 auto with air which is a numbers matching car. My engine is T0406 CTW. Is the Rochester Quadrajet the original? The number on the carb is 7042202 and below that is probably a serial number which is 02 DJ. Can anybody decode this? I saw a post not long ago showing that a half a dozen different carbs were used in 1970.

I can help with decoding the Rochester number:
704 ~ 1970 to 1975 Rochester
2 ~ year - 1972
2 ~ Quadrajet (4-bbl) Federal Standards
0 ~ Chevrolet
2 ~ Automatic trans (even number - odd numbers are manual trans).

Doesn't look like the original carb. There were probably a half-dozen original carbs for 70; Federal Standards emission, California Standards emissions, non-emissions, then one each above for auto trans and manual trans.

Dale: Thanks for the reply. I had a conversation with one of the owners back in 1983. He told me that the carb was taken off and a Torker manifold applied with a Holley carb. Apparently the original Q-jet was never put back on.