Sosige is correct. X is narrow. Non x is wide.
A/XA has the least difference between wide and narrow, F/XF has the most.
Having dual use split blocks just means less sets in your pit box and would be less expensive to fill your pit box with every conceivable option - but actually just as many parts....
Don't forget that when changing blocks, you are not only changing toe/sweep but also track width.
For example, for the rear using either X/F, XA/E (std) or XD/B would achieve 3deg of toe in. However, X/F is a very wide car, and XD/B would be very narrow.
To clarify on your questions;
Originally Posted by
Salkin
I have separate suspension blocks with 1C - 1XC marked on them. Guess these goes to the rear. But does the 1XC side sit closest to the centerline or closest to the edge of the chassis?
You sit the setting you are aiming for to the inside. So if looking for XC with a pair of C/XC blocks, mount the XC marking to the inside (toward centreline as you say)
For the rear blocks - front = closer to middle of the car
Originally Posted by
Salkin
The front specifies separate B blocks, but I only have blocks with 1B - 1XB marked on them. Does the setup sheet really mean 1B - 1XB blocks? And again, how are they mounted? 1XB side closest to the centerline or closest to the edge of the chassis?
Split blocks are always dual use, so yes, MR is using B/XB blocks, with the B marking to the inside/centre.
For the front blocks - rear = closer to the middle of the car
To explain what these mean in terms of "setting"
FRONT
-0.5deg of arm sweep (0.5deg "out")
Approx std width
REAR
3.0deg of rear toe (3.0deg "in")
2 steps narrower than std width