Hi all,

I recently picked up running ported NA 13B second hand for my car. Please could someone answer these questions for me. The motor has been running extractors

1) What is the purpose of the 2 little holes INSIDE each exhaust port (on the bottom)?
2) Are these hole supposed to be blocked?

On my engine 3 out of the 4 holes appear to be blocked but one isn't. I took off the metal blocking plate that is bolted to the top of the engine center plate and can see that there is a lot of carbon lining the inside of the center plate.

3) Would this carbon build up be coming from the small hole in that isn't blocked in the exhaust port?
4) Can I expect any damage to have been done to the engine because of this and do I need to make sure the hole is blocked before installing the motor.

Any advice greatly appreciated

 

Those are air ports for the emissions system. They are not supposed to be blocked.

The carbon lining in the middle iron is due to the EGR passages. It is normal.

 

Thanks for the reply. I am not running any emmissons gear. It is running a 48mm iDA and open headers into mandrel bent exhaust with 2 mufflers. So should I just leave the holes as they are?

thanks again