WIW 340 exhaust heat riser kit

2 1/4" butterfly. That should make it for a 340 or 360 unless it fits a big block. I'm not up on my counterweights but it looks like it could be from a big wedge.

It is 2 1/4” to give sufficient clearance..

Just measured mine in garage

77CE679C-0496-40DD-830C-1D54659AE144.jpeg

624B7F5F-9629-4930-A3AF-0F0BB361E078.jpeg

Here’s the 68-69 repro kit:

heatriserkit6669383440hp8361_6.jpg