BB Heater Box vs. SB/6 Differences

[ko-lek-tor]

I recently had a chance to compare my BB heater box to a SB. I thought they were both the same and the only reason the BB box had a different part number was because of the hose cover or clips or heater core or the rubber hose hole cover. So, I tried putting the core from the BB in the SB box. It did not fit. After closer examination, I found the one thing that is different between the 2 type boxes. The BB welded in heater core plate is approximately 1/4 in. wider. I could probably make the SB work with a BB core, but I would have to modify, I.E. hammer, to make it fit. Below is what I found. I hope this helps someone ID their box in the future. Bottom box is the BB one.

[Spooky]

Good info to know. Would you have measurements? I did not notice when I had mine out. Side by side would be noticeable.

Good job Bentley!

Scott

[jbtech]

Bentley thank you for identifying that bb and sb heater boxes are not identical. I'd like to add a measurement from my 1967 SS 396 heater box. The flange is noticeably wider here than a sb heater box. Can anyone add a measurement from a sb box?

[Driveway_finds]

I found this out the hard way!😂 I always look for the little bead roll inside the big block box to identify them!