[DeTomaso] Exhaust popping

[Fred Foreman]

After buying my Pantera, I had exhaust popping on deceleration with Hall "big bore" exhaust.  I was told about exhaust leaks too.
On checking over the system I found on #3 & #4 cylinders a black mark from leakage where the headers meet the cylinder head.  Removing the headers on that side showed that the header flange plate did not completely cover the corner of the exhaust port opening and the result was a burned thru corner and flange leakage.  So, My header primaries are much smaller than the cylinder head exhaust ports.
The correction was to weld up a bit on the edge of the flange plate to make it a wee bit taller and file it for a smooth sealing surface.

I have always wondered if my headers were really "big bore" or "little bore".  Does Hall make headers for 2 barrel heads with smaller ports?
Fred Foreman