I have two Holley master rebuild kits.  One appears to be for a 4100 4 barrel, 1957 carb.  What carbs/years are they intended for?  I don't have the instruction sheets.  They are 85R474S and 85R245S.  Thanks for any help.

Bill A

The 474 kit is for the LIST 1272 and 1273 Holly carb .That is a 57 T Bird carb with the 312 engine.

Your 245 kit is for Holly carb 885-FFC. Used on Mercurys from 49-51.
Fits Mercury carbs R652A,R679A and R690A

Info from my Holly MASTER REBUILD GUIDE.

While good kits in the day , with todays fuel they would probably last about 10 minutes.

Oldmics

Thanks John.  Should have asked you first.