I recently removed the headers from my 351C and realized that the flanges seem to be for a 2V head. The flange ports are smaller than the exhaust ports on my 4V heads and its causing carbon to build up in the engine.
I am looking buy a set of headers to replace these undersized ones, the primary tubes on my current pipes are 1.75"
This is going on a replica Lola T70 and the engine bay has quite a bit of room to work with. The engine is a closed chamber 4V (no dot) that was bought from Hall in the 1990's and its mated to a ZF transaxle.
I am located in the SF Bay Area, please let me know if you have an extra set of headers kicking around that you would like to sell.