Tubular manifolds have a tendency to crack, especially ones constructed of 304ss. You could take it to a welding shop and have them weld additional support between the flanges which helps a great deal, or hold out for one constructed of 321ss.thats not always true, different designed turbine housings with different volute designs will not be easily compaired by a/r. think about it, increasing r changes the ar value, but does it change top end? the restriction has not be decreased, and the only thing that might change is the velocity(component of velocity that is, aka the angle) at which the exhaust gases hit the turbine wheel. a gt3071r will have lower top end than a gt3076r, but not because the a/r is bigger, its because its the same exact turbo, and same turbine design, with a larger a/r.turbolarry said:There are six kits that are available from your link. Which one are you refering to? Keep in mind; The larger the area ratio (A/R), more lag it will have, but better exhaust flow, and more top end power. The smaller the A/R the more restricted the flow, a little sacrifice at top end, but better spool.
What exactly are you going for with your car?
As far as the above manifold?
