What are these ususual 2.7 Heads?

[tom1394racing]

I came across these unusual 2.7 heads in my large stock of 911 heads, They stand out as being unusual because they do not have either the CIS relief in the intake port nor an MFI bung. They appear to be carb heads and have an air injection bung in the exhaust port. The port and valve sizes are the same as the 2.7 Euro Carrera

Specs:
Exhaust port - 35mm
Intake port - 36mm
Exhaust valve - 40mm
Intake vale - 46mm
Casting stamp - 911.104.342.2R

Can anyone identify these?

[cgarr]

I have the same setting here right now, if you look closely you should see where the CIS relief is welded up, perhaps from the factory? I didn't notice it until the intakes were opened up to 37mm

[tom1394racing]

Craig

Thanks...I'll take a closer look.