When I bought my Zed I was handed the original rear boxes and 2 restrictor rings cut out of the exhaust pipe.I was told Nissan put these rings in to restrict power.This seems an unlikely thing to do after all that precision engineering.Does anyone know what they were there for?

Sounds a bit weird to me ? sorry its no help I know, but just so you dont feel ignored

Does anyone know what they were there for?

 

To restrict power.

 

Yes, you read that right..

 

They're there to restrict the exhaust flow - whether that was specifically to lower the power slightly (probably unlikely, there are easier ways for Nissan to do that) or to change the characteristics of the exhaust we'll never know. Probably there to make the exhaust quieter, but either way - removing them will help free up an ickle bit of power.

 

This seems an unlikely thing to do after all that precision engineering.

 

Ok it's a well engineered car, but I think that's overstating it a bit ;) Anyhow, they have power targets to meet - and in Japan, that means not going over 280bhp (at least it used to - the rule is still there AFAIK, just seems that they all get around it now by simply 'saying' their cars are 280bhp..), as well as targets relating to noise & comfort..

Yes i have heard that the jap imports have 1.5 inch restrictors in the exhaust somewhere near the main cat. Has anyone tried to take them out.

Yes i have heard that the jap imports have 1.5 inch restrictors in the exhaust somewhere near the main cat. Has anyone tried to take them out.

 

...... I was handed the original rear boxes and 2 restrictor rings cut out of the exhaust pipe....

 

I guess so :D