Can someone please tell me what adapter I need to put s fpss on the fuel rail test port? It looks like it will be a 4an female for the rail side to a 1/8 npt female for the fpss side. Is this correct? I need to order one but I want to be sure I am getting the correct one.

 

it is a 4an

 

Usually the adapter comes with the FPSS - but what you need is the adapter that has -4AN female one end, -4AN male the other end, and has either one or two 1/8FNPT ports in the body to screw the FPSS into. All the nitrous sponsors sell em'

BTW, they make two versions of this adapter - one is a swivel (which will allow you to 'clock' the position of the FPSS prior to tightening down, the other adapter is solid.

 

Like suggested above.
Here are two different ones.

Swivel
http://www.nitrousoutlet.com/catalog...roduct_id=2696

Non Swivel
http://www.nitrousoutlet.com/catalog...roduct_id=2717

Dave