Heat Riser 2.5 inch for a 67 BB

[Daniel E.]

All,

I thought the heat riser on the left was the original to my car but after finding the one on the right, I am not sure. Notice the plug at the end of the valve shaft. Is one more correct to what would have been on the car from the factory?

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Thanks
Daniel

[Daniel E.]

Re: Heat Riser 2.5 inch for a 67 BB

I am surprised no one has responded. With the NCRS attention to details, I can't believe this difference would have slipped through the cracks. I have continued trying to verify which item would be a "typical factory" item but have been unsuccessful.

Any opinions or facts to help?

Thanks
Daniel

[Gene M.]

Re: Heat Riser 2.5 inch for a 67 BB

Daniel,
I've seen the two inch size in both configurations. I've not experience looking for 2 1/2" size that I would look for the plug. But I suggest GM had multi supplier source on this part and you are just seeing production differences. I can tell you I've seen variations on the swing weight as some don't have ID markings in casting. At least this will move your post back to top.

[Stephen L.]

Re: Heat Riser 2.5 inch for a 67 BB

I believe I identified the part# on the "new" heat riser as correct for a BB in an earlier post. Number ended in "44". I looked at my 67 BB with a relatively new (last 20 years) heat riser installed and it doesn't have a "thru shaft" (no plugged hole). The original cracked and I replaced it. I don't recall if it had a thru shaft. So, as Gene said, more than likely there were multiple suppliers and both were used. Now the decision: Go with the new and get the correct part# or go with the used one because it has been previously installed someplace....

[Daniel E.]

Re: Heat Riser 2.5 inch for a 67 BB

Gene and Stephen,

Thanks for the information. Both heat risers have a number ending in '44'. Also, the heat riser that looks new is actually one that I restored.

Daniel