R56 or GP trailing arms on R53
 

anyone know if swapping r56 or r53 GP trailing arms onto an R53 is legal in STX? I think it is but just wanted to clarify.

also if anyone did this, does it give more inside wheel room so I can fit more tire?

Yes I know you will have just a little more room for the tire with the Aluminum arms. But not sure if it is against the rules or not. The GP did have aluminum arms so I would think it would count as update/backdate.

You will need are spacers to install the shocks though.
http://waymotorworks.com/wmw-rear-shock-spacers.html

Unfortunately, that's update / backdate which is not STX legal. It is legal in SP, though.

STX allows control arm changes but the rear has all kinds of crazy regulations/rules, someone got it approved years ago by a board member but that's all I could find

Here is the rule for STX

On double/unequal arm (e.g., wishbone, multi-link) suspensions, only the upper arms OR lower arms may be modified or replaced, but not both. Non-integral longitudinal arms that primarily control fore/aft wheel movement (e.g., trailing arm(s) or link(s) of a multi-link suspension) may not be replaced, changed, or modified.

Can't change them. The rule is intended to allow cars that can't get camber more camber. For the rear you can use an adjustable upper or lower lateral link, but not both. You can also change bushings.

All the confusing language in the rest of that section is to keep people from using the allowance to do stuff other than get more camber.

scca rules suck, if all we are doing is getting more tire width and still well under the limit they should allow it

If you really want to update / backdate that bad you can run DSP. It's legal there.

nobody runs that class here, that's also a Hoosier class so no thanks!