After a lot of research I was under the impression that 15" wheel cars (or those with sport suspension) had the WS steering box with the quick 12.7:1 ratio and 70* turning radius and the 16" wheels had the XH box also with the 12.7:1 ratio but with a narrower turning radius (64*) due to the wider wheels. I also was under the impression that along with that the steering stops on the control arms were different as well.

I had 15" trans am wheels and the quick ratio (factory) and i am pretty sure i can faintly make out a WS on the box. I am putting on 16" formula rims and a box out of a 91 GTA that i can see an XH on it, however, when i put this new box on, the wheels still turn the same distance and hit the current stops on the control arm.......what gives? I was all ready to modify the stops because i though these boxes had a different turn radius. WHat exactly is the difference between them then?

 

My '92 RS with the factory 15" wheels has the JL box. Which is an OK box.

Some info I have on the XH & WS boxes:

Both have the same 12.7 ratio

XH is higher effort at 28 - 34, with 32* in each direction
WS is lower effort at 24 - 30, with 35* in each direction

I guess the 3* less in each direction doesn't make enough of a difference to prevent hitting the stops.

RBob.