The seats that were installed for the ex were too big really.
And if you look close you can see the edge that was left around the perimeter of the seat has been hammered/folded down over it.
Both the OD and ID were incorrect.
These were T/A heads, and the ex seats weren’t worn out, or leaking coolant....... so I decided to leave well enough alone and just blend the bowl up to the insert to get rid of the ledge where the insert meets the port.
The intakes flowed mid-230’s, but even after blending the ex were still only in the upper-150’s(about 5-7cfm lower than if the correct insert had been used......... so, not the end of the world).
Street duty pump gas 416/6bbl..... about 450hp with a pretty small solid lifter cam.
