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Classing question for Autocross

Old 07-03-12, 04:28 PM
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Classing question for Autocross

I currently run a 1985 RX7 in CSP. Over the winter, I added two items that will move me out of CSP, but I'm not sure what class it will put me in now. The items in questions are:

1. Turn in spacers (roll center correction blocks)

2. A triangulated front strut bar (mounts to firewall)

I'm short on time, so if anyone is willing to take mercy on me and give me the easy answer, it would be greatly appreciated. Thanks for your time.




.
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Old 07-03-12, 10:46 PM
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SSM I imagine.
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Old 07-03-12, 11:21 PM
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SSM is correct, judging by my quick scanning of the rules. (SCCA March 2012 rules)

Ahhh, you have entered a realm of large possibilities now, my friend!

Unlimited brakes, any size fuel tank (must be 5 gal), you can add a rack and pinion, any suspension that retains stock mounting points, maybe a little porting for the ol' 12a?? etc...

This is what I last ran in, since whenever I built the engine I didn't take into consideration the engine restrictions of SP class. I'm completely uncompetitive, but that's a million reasons why, not just the engine.
I think it would be fun to move your car up, but also think that now any kind of induction and engine configuration is open, as long as it's still the same manufacturer. So you may not be "competitive", but hey, if it's fun go for it!

Good luck!
-Max
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Old 07-04-12, 06:01 PM
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Well, I was already scrapping with the SM/SSM guys anyway, and even got a few victories off of them last year. With the difference that the turn in spacers have made, I don't think I'll need much more of anything to take them on now.

The only issue will be courses with lengthy straights where they can use their excessive HP to make up for my handling.

Thanks for the input...
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Old 07-04-12, 07:39 PM
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You sure SSM? I thought any triangulated bracing (OPs front strut bar) shot you straight to the prepared classes?
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Old 07-05-12, 01:28 AM
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Not sure about the spindle spacers.

The way the SM rules are written it seems like you can add a brace between the struts OR you can retain/modify a trangulated brace if the car came with one. To me this means that if your came with no brace you can add one that attaches in two points. The Strut brace rule in SM is based on ST and SP rules.

To be sure, download the latest rule book.

I run my 85 Mustang GT in SM because I have spherical bearings in my rear suspension. My personal opinion is that the SM/SSM rule set is kind of messed up and always has been. It allows you to do allot to your car in some area but there are restrictions that don't make allot of sense. Basically the rule set favors light cars with forced induction. A RX7 should be a good choice and a Mustang not so much......
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Old 07-05-12, 02:26 PM
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ohhh triangulated bar, ya no bueno for SSM. since its just local events it doesnt really matter anyway. I highly doubt you guys have protesting..

But if you wanna keep it legit, I'm pretty sure you're knocked into FP (or XP)
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Old 07-05-12, 05:19 PM
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Yeah, I seem to be the only one worried about it (classing/protests/etc). Great bunch of guys.

Thing is, CSP was becoming a pretty big class for our area, and they were all pretty evenly matched and it was good racing. Until I got off the Sumitomos and threw on race rubber, that is.

After that, everyone else was just racing for 2nd place. I didn't want to kill the class by taking the fun out of it (or by forcing the others to invest in race rubber), so decided to move up into a class full of cars I could "sometimes" get the best of as the car was (I had 3 FTDs last year with the Hankooks).

I don't want winning to be easy, I race for the challenge. Otherwise, I'd just drive a Miata.

Maybe I'll remove the extra bars from the strut brace, and race in SM or SSM (whichever would apply). We don't have anybody racing FP/XP in my area.

Even with a stock 12a, Sterling carb, Respeed suspension, I was able to take on supercharged Miatas, 911s, Corvettes, and just about anything else that showed up. Not beating them, but definitely snapping at their heels.

I wanted to get an extra edge this year, but through handling rather than horsepower. Hence the new parts. I really can't tell if the strut bar makes any difference or not, but good God did those roll center blocks improve things!

Last year I could tell that while turning through a corner, the front wheels were not lining up in the correct direction due to the lowered stance of the car (fighting each other, scrubbing). I had to slow down quite a bit to keep the front end from washing out on me in corners. It also acted like I was using the front brakes through the turns (due to the misalignement of the front wheels), which made the tail want to come around on you fairly easily.

After the race last Sunday, I had to learn to drive all over again. No matter how far I turned the wheel, or how fast I was travelling, the car simply went there. Speed through the turns is greatly improved, and the tail happiness is GONE. For the first time in years, I was getting scared and having to force myself to keep the speeds up and trust the car.

Hard to believe the difference such a small part can make.

These are the roll center correctors I'm talking about (they mount between the control arm and the strut, lowering the control arm for correct steering geometry). RE-Speed Suspension Parts : 1979-1985 RX7 Roll Center Blocks, Pair

Thanks for the input guys.
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Old 07-06-12, 06:26 PM
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Sorry for the misinformation Kentetsu, I got mixed up reading the pdf.
Glad to hear the roll center blocks worked so well! That's very encouraging.
Are you still running the 13'' wheels? What rubber do you plan on running this year?
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Old 07-06-12, 06:30 PM
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No problem man.

I'm running 13x8 wheels with Hankook race rubber (forget the name at the moment). 30% cheaper than the Hoosiers, seem to wear MUCH better, and the grip is unbelievable. They've got about 8 events on them, and still look nearly new.

The guys running Hoosiers always come over to see what I'm running. I think there will be many racers moving from Hoosier to Hankook this year in my area. No other way they're going to catch me.

Okay, here's the link to the tire I'm running. I paid 140 each, installed, at Discount Tire (they are very hungry for business, and will beat any deal). Hankook Ventus Z214
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Old 07-06-12, 07:26 PM
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Wow, that's a deal!

Do you think using the heim-jointed lower links in the rear like what re-speed offers would provide an advantage?
I drove Billy's widebody with them before he sold it and it felt so solid and direct. At $250 I wonder if they would be worth a shot...
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Old 07-06-12, 07:34 PM
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I had a set of those, but never installed them. Now I can't find them, so I think I might have given them away to someone in need at some point.

Having said that, it would probably be one of the last mods I made to the car. Coilovers, camber plates, swaybars, turn in spacers, etc. will make a bigger difference if you don't already have them...
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