spec twins class in SCCA solo2
 

There was a mention of forming a spec twins class in SCCA Solo2 in the most recent SportsCar magazine issue. Let's start a discussion about what modifications would be ideal to form this class.

I haven't given it a bunch of thought yet, but I'd say it could fall somewhere between DS/CS preparation and STX with a focus on making the cars as fast as they can be while still keeping the costs and rule set to a minimum.

:cheers:

Guess I shouldn't have tossed mine into the recycle bin like I normally do.

I would take a step back before discussing modifications and ask "how spec do we want this to be?" In a true spec class, most of the major parts are fixed: you specify springs, shocks, swaybars, and tires to use. Costs are reduced both by selecting budget parts, and by reducing the need for you to test eleventy billion combinations of suspension parts.

Aside from that, yeah, I'd look at doing something like STX-lite.

How specific are the rules usually? Like, would you choose a coilover package, or just say "single adjustable" ... My experience says it gets very specific about parts, but not with how you set them up, so say RCE T2 with RCE tophats , but you get to choose alignment and shock settings.

I'd lean away from header and tune or some of the weight redux STX allows, so C/DS with spring and alignment improvements, and probably wider wheels/tires. That should extract more out of the car without a substantially bigger budget than CS.

My stab at it:

Intake: OEM, any filter
Header: select from approved list, or OEM
Overpipe: any
Frontpipe: OEM
Exhaust after front pipe: any
Tune: reflashes only
Springs/shocks/sways: spec part for each, or OEM
Camber plates/camber bolts/top hats: any
Wheels: any 17" or 18" wheel up to 9" wide
Tires: any 200tw up to 255mm
Diff: OEM
Minor allowances: I'd pull in a lot of the Street stuff like changing studs and so on

As I've built it, this ruleset would allow showroom stock cars to play (a lot of true spec classes don't even allow that, you must convert to their package entirely) as well as street class cars. You get most of the fun stuff (more power, more grip) for a lower price than a fully competitive entry to STX.

I would caution, however, that this may suck numbers from STX and Street rather than build up a new pool of entrants. It's an unfortunate reality that classes don't exist just because they're a fun idea, but also that they serve the needs of the club's members AND help drive additional growth.

I'd be in favor of header and tune. The extra power and death of the torque curve are a large part of the STX fun factor to me.

I'd add brake pads and a oil cooler. This is a good start for the discussion.

Brake ducts: any. BBK: no.

I think wheel width allowance would depend on spring/coilover allowance. IIRC, fitment of 9" wheels would be limited with stock size springs. Maybe if stock or stock-ish springs only allow up to 7.5" or 8" wheels. At it would be enough wheel width to square up a tire and get better wear. Camber bolts would help too.

A lite-mod spec class would sure bring in the class numbers, I think.

I would say:

Intake: Open, must be fit without cutting or trimming
Header: OEM
Overpipe: OEM
Frontpipe: OEM
Catback Exhaust: any
Tune: reflashes only
Springs/shocks/sways: OEM Type Spec Springs (Swift, Eibach, TRD), shocks: Spec Koni Yellow (single adjustable), bumpstops: any
Top Hats: OEM
sways/endlinks: any
Alignment: Front Camber Bolts (any), Rear LCA
Wheels: 17x8" any offset
Tires: up to 245 wide, 200tw
Brakes: Lines and Pads open. Rotors: OEM
Diff: OEM
Minor allowances: Street hardware and comfort/convenience allowances

I think it would be pretty good back for buck. It might appeal to the enthusiast with common mods and still have good multi (daily street/track/autocross) use without much maintenance headaches.

Camber plates can make things funky as they sometimes can require custom front endlinks or limit front sway bar fitment. Camber bolts would be cheap.

I would say save the bigger power mods (header, etc..) for STX...otherwise the class might have a mass exodus!! LOL!!

I have no idea what this discussion is about as I know nothing about spec classes and didn't know they could exist for autocross....

But I'd say Koni yellow, 17x8 wheels, tires, header, tune, front/rear sway bars, drop-in filter, camber plates, and brake pads. If they need to be specific.... have vendors bid on their product being selected and they give a discount to class participants on those specific products.

That would put the total prep cost around $7,000 not counting alignment.

I think the class would need to bring something to the table you can't get in CS as far as handling, without approaching STX, which is why I say no header or tune, but proper alignment and spring rates from coilovers. Also considering something that would be 100% warranty compatible. That leaves header and tune of the table for me. It means Toyota or Subaru could get on board... But maybe they would anyway? Or not...

On that note, the performance package has to be considered re: brakes, though I don't know that's more than heat capacity at best... Weight at all?

I'd be disappointed to spend that much and not have coilovers.

Maybe make it OTS OFT only for tunes, so they're easy to open and inspect. I still think tune isn't right. 8" wheel and 225 tire is interesting though.

I agree it needs to be something between STX and CS. And a main point is to allow interchange of FRS and BRZ parts so things like a trunk swap can't DQ people cuz they have the other manufactures factory spoiler

Intake: OEM, drop in filter
Header: OEM
Overpipe: OEM
Frontpipe: OEM
Catback Exhaust: any
Tune: EcuTek spec tune
Springs/shocks/sways: Spec spring/strut combo (Swift Spec R w/ Koni Yellows) w/spec front sway
Top Hats: Stock
endlinks: any
Alignment: Front Camber Bolts (any), Rear LCA
Wheels: 17x8" spec wheel
Tires: 225 or 235 spec tire
Brakes: Lines and Pads open. Rotors: OEM
Diff: OEM

Any spec part can be replaced by OEM as well. No light seats or battery. Comfort/convenience allowances. Oil coolers OK. STI lip kit (with alternate FRS front lip) is optional to protect everyone's bumpers and side skirts haha

To me the header/reflash is basic kit for this car. Adds no weight, fairly easy to install yourself, removes nothing from the original design intent.

Spec the Koni yellows, remove the camber-limiting insert,TRD springs, any cat back or at least spec one that is not loud.

I like coilovers, but rake, and corner-balancing adjustments (or the lack thereof) can render very different animals from car to car. Every driver should have some space for "tuning" to their own driving style but I think alignment and a set of (spec) adjustable sways could cover that and keep costs (and complexity) down.

Interesting. A couple years back a letter was written for something similar. MSP - Miata Street Prepared. Place for all the miatas to play, with the idea that it'd finally spur some folks to build a (srsbzns) CSP car that wasn't a Miata. Miatas still come out in numbers, and likely enough effort to see at least a couple CSP twins, and maybe a few folks dust off their CRX. Generally all additive, with a screwing over of no one.

The response was slightly longer-winded, but it was still effectively "Thank you for your input."

As for Spec Twin? It seems like a good idea, but the devil's in the details. This isn't road racing, but Spec Pinata has shown us all that "Spec" frequently encourages rules interpretations that are...creative. And there's more to cost control than just a parts list. All you need is one person to do very well, and that person say something like "I only run sticker tires" and the spend-a-thon is on. It's hard for a rules-making committee to control for that.