Alfa 2000 engine question

[Skyedriver]

Was looking through some photos of a car for sale and wondered what the 4 screws/bolts were for in the exhaust manifold. Any ideas?

[oakdale]

In some earlier emission control systems a pump was used to inject air into the exhaust ports to help with the combustion of unburnt gases (only in certain markets), I think that's what they are for.

[snotrag]

Could also be Lambda sensor or EGT sensor ports used for tuning - allowing for proper tuning of individual cylinders.

Once finished, pop a blank in.

Particularly likely if it has a fancy/aftermarket ECU. Or just that the exhaust manifold they bought is ready for it, whether its been used or not.

[Scrump]

Skyedriver said:

Was looking through some photos of a car for sale and wondered what the 4 screws/bolts were for in the exhaust manifold. Any ideas?

The bolts are there to plug the holes in the manifold.
HTH

[Skyedriver]

Thank you oakdale and snotrag, that explains that. Not something I'd seen before.