BB GM Heat Riser # 3940977

[GaryC]

In case anyone needs to know this info, I just happen to look in my 1969 Impala A.I.M. and found the part number for the heat riser John Brown posted a pic of and is the same as what I have 2 of... Part #3887024. I Googled the number and found this ebay link...

http://www.ebay.com/itm/NOS-GM-3887024-H...#ht_3282wt_1007


and this link that indicates what that part number was used on...HR024.


http://www.hamiltonmanufacturing.ca/hrv.htm

I hope this helps everyone out. If anyone has a used 3887023 I have the 2 3887024 I'll trade you.

[John Brown]

Gary, the 3887024 valve on ebay is mainly for a small block. Look down further at the applications he shows from GM parts books. No doubt it's for a 2" exhaust system. The one I posted pictures of is a 2 1/2" valve for a big block. As I posted above, the 3746844 number on the weight is generic, same as the ebay seller says. It was used on both big block and small block valves.