Mods allowed for H Stock

R

Rotaryknight

:
2012 Mazda2 Touring 5sp, 1989 Rx7 GTUs Turbo, 2012 Yamaha FZ8
I will be doing a full season of Autox with my Mazda2 and I was wondering what kind of mods are allowed in H stock?
Being competitive is nice, but having seat time is what I am aiming for.

Any leeway for tires sizes? From what I gather, 195/50/15 is the best size for the tires, and it must be a rim that is the same size as stock? So if I get Toyo R1R on any Rim that is the same as stock, I am good?
Would it be better to get all 4 tires, or just the fronts?

Suspension wise, I guess corksport adjustable shocks are illegal? Are spring changes illegal? Adding a rear torsion bar is legal though right?
 
Wheels must be the same size, and probably (I'm not 100% sure on this) the same offset. If you're going to have a dedicated wheelset, you'll want to go with an r-comp such as the v710's rather than a street tire. That is unless you are going to be in RT-FWD in which case the 195 R1R's are banned. And you want good rubber on all 4 corners. Also, the adjustable dampers are definately legal. There is an allowance for a front OR rear swaybar. Technically, a torsion bar is NOT a swaybar, and not legal (though I highly doubt on a local level anyone will protest). Springs must be stock. No camber bolts. Cat-back exhaust is free.
 
I think you have 5mm off set allowance on the wheels, K&N air filter replacement is allowed has to fit in the factory box.

Andres
 
R1r is legal though right in h stock on same size wheel? I will probably go with them with a dedicated wheel set, and corksport shocks and catback
 
I heard that they were contemplating on whether the rival was going to be legal by end of April?

How about the star spec II, or the re-11. They are about the same price

I have tried the first star spec and liked them,.
 
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Tires have to be DOT approved in the stock classes arent they? The only one that I've seen for 195/50/15 is the R888 unless I go to 205 width.
Main reason is money though lol, they are too expensive.
 
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you can (and should) stray from the ideal size to get the tire model with the grippiest rubber in most cases. 195/50 is so popular partly because the r1r rubber is manufactured stickier in that size throughout more of the tire. Keep in mind, aside from driver skill, tires have the biggest impact on lap times.
 
I'm not a 2 owner (yet) but have been thinking about an HS setup for one. What wheels are guys running on the 2's? I haven't really found too many of the popular light weight wheels offered in the stock width.
 
Meat said:
I'm not a 2 owner (yet) but have been thinking about an HS setup for one. What wheels are guys running on the 2's? I haven't really found too many of the popular light weight wheels offered in the stock width.
Click to expand...

I did some digging and I didnt find much either. I wonder if you can use the 14 inch miata wheels from NA chassis cars, they are super light.

-Derrick
 
I'm pretty sure SSR has something in the stock size, I can't remember the offset though. Nevermind...as I started to type this I'm remembering it was 15x6.5. May have to go custom. I doubt 14" is legal since the 2 only comes with 15's.
 
Wanted to stay legal if I decided to do H Stock. Found some D-Force 15x6 wheels (11.8 lbs) at Phil's Tires (advertises racer stuff); Needs hub centric rings for sizing & spacers 5mm) for front for clearance. Using with 195x50 new Dunlop Direzzas. Just on this week. Will try out next weekend at Buttonwillow at least for road course use.
 
racercentral said:
Wanted to stay legal if I decided to do H Stock. Found some D-Force 15x6 wheels (11.8 lbs) at Phil's Tires (advertises racer stuff); Needs hub centric rings for sizing & spacers 5mm) for front for clearance. Using with 195x50 new Dunlop Direzzas. Just on this week. Will try out next weekend at Buttonwillow at least for road course use.
Click to expand...

These? Not too bad for a bit over 1 Benjamin each.

DForce-and-Lizzie.jpg
 
I breifly thought about getting a set of those d-force wheels for the miata. The SM crowd seemed to think highly of them from what I read, they ought to hold up very well. Should be a fantastic h-stock wheel for the 2.
 
Do a search for scca 2013 solo rules. There are two classes: HS and RTR HS. The toyos were banned in rtr but are legal in HS but not as fast as r-comps. At a local level looking for seat time you should concentrate on seat time and learning how to manage tire temp and pressure settings. Get a notebook a go pro and a DL1 data logger to understand what is going on.
 
195-50-15 in re-11a or z2 Dunlop are fast tires. I have the 205 advans and they are heavy but fast. You can also get different dampers. If money is ok try a set of custom Penske or moton's.
 
Rotaryknight said:
I will be doing a full season of Autox with my Mazda2 and I was wondering what kind of mods are allowed in H stock?
Being competitive is nice, but having seat time is what I am aiming for.

Any leeway for tires sizes? From what I gather, 195/50/15 is the best size for the tires, and it must be a rim that is the same size as stock? So if I get Toyo R1R on any Rim that is the same as stock, I am good?
Would it be better to get all 4 tires, or just the fronts?

Suspension wise, I guess corksport adjustable shocks are illegal? Are spring changes illegal? Adding a rear torsion bar is legal though right?
Click to expand...

Suspension mods will turn it into a H-Street Modified class. These include lowering swprings, sway bars, adjustable shocks, etc.
A or R compound tires would also make it a H-street modified class.

But you can install better high performance tires for racing in H-stock, as long as they are street legal tires.

And I think exhaust systems are allowed for H-stock if they still utilize the catalytic converter.
 
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