whats this thing on my manifold? important peice? thanks

 

Twin scroll flapper arm. There are debates on whether or not to keep it... rather than hear everyone's parroted opinion on it, just do a search for "twin scroll removal".

 

remove it

 

You will be sorry..

 

please explain

 

I didn't hear you explain why you should remove it...

S13 Slide, the purpose of the twin-scroll flap is to block off one of the turbine's scrolls at low revs. Because exhaust flow is low, velocity is also low. By blocking one scroll off you increase the gas velocity, which spools the turbo up quicker. At 2700rpm the flap opens and the exhaust gases pass through both scrolls.

On a stock or mildly modded engine it should be kept.

 

CHECK PLEASE!!!.........

 

all that thing does it eat up gas!!!...making you boost when you don't want to and what not, if you have intake and full exhaust, once removed my mpg went from 15-17 to 18-20, unless of coarse my foot is stuck to the floor...

 

Yeah, and its fun to wait all day for boost too..

If gas mileage was an issue, I would drive a Honda.

 

Lowering performance will usually lower fuel consumption too...