on a B16, a .63 wont really spool till 4500 im guessing. Shit, a .63 AR is what i would use for MY supra, and thats a 3.0 liter. a 1.6L is gonna have a helluva time pushing enough air thru that big of an exhaust housing, even if it is like 9.5:1 compression stock... or whatever the hell CR B16's come with.

a .63 AR is basically useless on the street and only good for maybe Drag racing... if you have a stutter box and N20 to spool it off the line. thats gonna be a huge single thats gonna be nothing on the bottom end and give you everthing on the top end... like a Supra power curve running a T88... i just hope you are geared for 180mph, cuz thats about what youll be running... its only good for a high-way warrior.

the way you can tell the AR of a turbine housing if its not obvious, is to measure. basically, you take the Area of a given cross section of the turbine. and divide it by how far away the center point of that cross section is away from the center of the turbine housing, the Radius.

A turbine housing is like a Funnel only wrapped around a center axis; the turbine wheel. If you unwrapped it, it would look like a cone, and the smallest side is where it ends. the biggest hole is where it bolts to the manifold collector. If you measured the area of the hole at any point in the cone, either close to the narrow end or the wide end, it wouldnt matter. Once you have that measurement of the area, take a measurement of the distance from the centerpoint of the cone (where you measured the cross section of the cone) to the center of thee turbine wheel. that will give you your Area-to-Radius ratio. since its a ratio, its the same value as long as you measuer from the same 2 points... if you measure the area of the turbien inlet, and then measure the distance from the center of the small end of the cone/funnel to the center axis, youll get the wrong answer.