This is a Very Hard to Find Very Sought After Small Block Non EGR Chevrolet 2bbl Intake Manifold for Circle Track Applications where rules require Cast Iron Manifold, This is one of the best Flowing SBC Manifolds. No Porting or Grinding! All threads in nice shape with No Helicoils etc. Part # 6263752. Date code Sept 23 1971. I have Several Big Bore 2bbl Intakes for sale as well with the following Casting Numbers 3916313 346260 6266752 3973467   

Circle Track IMCA WISSOTA NASCAR BOWTIE BRZEZINSKI