Gen 2 Autocross Classing | Write your letters!

[timurrrr]

PSA for people who plan to run aftermarket RLCAs in the ST* class in the future
All gen.1 RLCAs are likely illegal on 2022's, because the distance from the subframe bushing to the strut attachment point are different by ~0.5".

Originally Posted by timurrrr

gen.1:

(DM me for credits, I don't know your forum handle!)

2022 BRZ:

(Credits: @trippinbillies40)

[racingfool]

This would be a fun B Street Prepared car.

[Brock H.]

Originally Posted by timurrrr

PSA for people who plan to run aftermarket RLCAs in the ST* class in the future
All gen.1 RLCAs are likely illegal on 2022's, because the distance from the subframe bushing to the strut attachment point are different by ~0.5".

That image is messing with me a little bit and I can't read the measurements due to the lens fisheye. Is that saying the older arms are longer?

[timurrrr]

Originally Posted by Brock H.

That image is messing with me a little bit and I can't read the measurements due to the lens fisheye. Is that saying the older arms are longer?

I agree the angles on those photos could be better, but the important bit that's somewhat more visible is that the distance between the axis of the inboard/subframe bushing and the hole for the strut bolt has changed by ~0.5" between generations.

Not enough to make any difference that most people would notice, but sounds like it technically violates the ST* rules.

I wonder if SCCA would be open to make an exception here.
RLCAs are already pretty expensive, and I can only imagine that the need to design, test and manufacture a new variant for 2022's will not make it any cheaper.

[ka-t_240]

I want to see them both off of the car, and properly measured. Seems odd that they would change the length.

That being said, most of the arms on the 1st gen adjust camber by becoming shorted/longer, so the same argument can be made that they are not legal either.

[Breezio]

Originally Posted by ka-t_240

I want to see them both off of the car, and properly measured. Seems odd that they would change the length.

That being said, most of the arms on the 1st gen adjust camber by becoming shorted/longer, so the same argument can be made that they are not legal either.

This has been covered many times. The standard adjustable rear LCA's are not illegal. It's covered in 14.8.H.5

"The replacement arms or mounts must attach to the original standard mounting points. All bushings must meet the requirements of Section 14.8.B. Intermediate mounting points (e.g., shock/spring mounts) may not be moved or relocated on the arm, except as incidental to the camber adjustment. The knuckle/bearing housing/spindle assembly cannot be modified or replaced."

[Kelse92]

Aren’t there a handful of RLCA options that offer multiple pickup point options, so you could choose the hole that matches? It’s been a while since I looked..but SPL seems to ring a bell with being one of them. Granted, a higher cost and need to swap out the spherical ends but could be a possible alternative?

[timurrrr]

Originally Posted by Kelse92

Aren’t there a handful of RLCA options that offer multiple pickup point options, so you could choose the hole that matches? It’s been a while since I looked..but SPL seems to ring a bell with being one of them. Granted, a higher cost and need to swap out the spherical ends but could be a possible alternative?

But the hole you're using must precisely match the location on the 2022 stock RLCA. I presume none of the holes on the SPL match it precisely.

[Breezio]

My opinion. You'd have to look at the measurement on whichever end of the LCA isn't adjustable. If you can get that to match the factory measurement, you should be golden.

[Autoxer62]

Originally Posted by timurrrr

But the hole you're using must precisely match the location on the 2022 stock RLCA. I presume none of the holes on the SPL match it precisely.

Fair enough, but a decent fabricator could weld the holes shut and re-drill them to the new position.

[DocWalt]

Originally Posted by Breezio

My opinion. You'd have to look at the measurement on whichever end of the LCA isn't adjustable. If you can get that to match the factory measurement, you should be golden.

That's not how the rule is worded. Moving the shock hole in relation to the fixed end is illegal, no matter which end is fixed.

The camber adjustment end does change the shock hole in relation to that end... but the rule specifically says that's legal as noted above.

Originally Posted by Autoxer62

Fair enough, but a decent fabricator could weld the holes shut and re-drill them to the new position.

Right now, this is the only legal fix for *any* of the aftermarket RLCAs from a first gen.

[Kelse92]

Originally Posted by timurrrr

But the hole you're using must precisely match the location on the 2022 stock RLCA. I presume none of the holes on the SPL match it precisely.

I’m just offering if someone has one it might be worth measuring.
This is supposed to be easy “bolt-on” modifications, nobody wants to be welding/fabricating stuff if we don’t have to. Drilling a hole is simple enough but I dunno, trying to make things simple

[DocWalt]

I'd be all for the STAC making an exception for this, but it's a can of worms where all of these little things could be added up and make for a faster car so I get why they'd not want to.

In any case, my car will be on stock rear arms or I'll find someone to weld/drill some cheap BLOX arms or something.

[strat61caster]

The lca and the charcoal filter both exemplify the worst of the scca rules and the pages and pages of nitpicking prove why the rules are the way they are.

This lands squarely in the 'idgaf' land, people with more energy then I can hash it out, I'm not losing because of a half inch change in damper attach point (which in ST is completely moot since you can run whatever springs you want) or 2.6hp