WRX1986

Hi All - I'm relatively new to Autocross, having run a handful of events in Novice over the past two years. I absolutely love it, so am trying to become a bit more mindful of classing as I go through the list of mods that I currently have and/or might be adding in the future. I believe I have myself narrowed down to either STU or XA, and while I would prefer to run in STU, there are a couple of items that may prohibit me from doing so. That's where I'd love your opinions on the matter, so below is a list of the items that I think might knock my out of STU - and if that's the case, then do you agree my next best option would be XA...even though I wouldn't be competitive at all in XA? At the end of the day, I'm just competing against myself, so honestly I just want to know what class I should be in so as to not be cheating in any way.

- Z1 Rear Subframe Collars (SCCA 14.8-K "Subframe mount bushings may be replaced, but must attach in the standard location(s) without additional modification or changes. Subframe position may not be changed. Solid metal bushings are specifically prohibited.")
- SPL Compression Arm Spherical Bushing (SCCA 14.8-B "Suspension bushings may be replaced with bushings of any materials as long as they fit in the original location. Offset bushings may be used. This does not authorize a change in type of bushing (e.g., ball and socket replacing a cylindrical bushing) or use of a bushing with an angled hole whose direction differs from that of the original bushing. If the standard bushing accommodated multi-axis motion via compliance of the component material(s), the replacement bushing may not be changed to accommodate such motion via a change in bushing type, for example to a spherical bearing or similar component involving internal moving parts. Pins or keys may be used to prevent the rotation of alternate bushings but may serve no other purpose than that of retaining the bushing in the desired position.")
- Bell Raceworks Diff Brace (this one is really throwing me for a loop - I can't seem to find any details on something of this nature in the SCCA Classification guide...)

iideadeyeii

iTrader: (6)

How I and the courts would interpret it
Z1 Rear Subframe collars would be an additional modification
SPL bushings change the type of bushing
The diff brace adds to where the diff is mounted and is not a standard location

WRX1986

Dang, guilty on all three counts. I guess the positive here is that I was able to accurately interpret the guidelines. So I guess XA it is for me, when I graduate from Novice that is. Or is there a class I may be overlooking that would be more appropriate?

Thing is I just ordered some HFCs to replace my test pipes with the hopes of classing down into STU, but realistically I didn't love the noise level and environmental disregard for emissions that came with the extra 1-2hp of test pipes, so I'll still count the HFCs as a win in my book. Also XA would allow me the freedom to replace/upgrade in the future without worry of outclassing.

iideadeyeii

iTrader: (6)

Honestly, I know nothing about the classes, but why not change the bushing to solid, but not metal to stay down?
On the other hand, if you are just competing vs yourself, do what you want and go with the appropriate class for your mods

WRX1986

That is an option, but if I swap out the spherical bushing then I'm still pushed out of class by the subframe collars and diff brace. But you sorta hit the nail on the head, I'll mostly be competing against myself at these events and even if I make these changes - STU is still a class that I would likely not be competitive in. At the end of the day, this car stills split duties between a weekend cruiser that sometimes hits cones on an AutoX course. The other thing that comes to mind is any future mods/maintenance; if I want to go the STU route, I'm limited while XA allows mostly anything. A couple examples that came to mind which are realistically going to need to happen in the future are a CSC Relocation Kit and flywheel replacement. I'm not 100% sure on the CSC, but most kits come with a SS clutch line which you cannot have in STU. And for flywheels, you must replace with OEM or OE equivalent (clutch and pressure plate can be changed) - and I don't know that I'd want to do that with some of the options that are on the market, both for performance reasons and cost reasons.