I attended an Evolution Driving School this weekend, and have become addicted. Currently I'm running a 1986 Sport with an 89 motor - which should put me in STX (or F-Mod, but I don't want to go there). My local SCCA chapter said they'd run me as E stock until I changed other stuff or went futher than the local/regional level. My goal is to slowly mod the FC into the STX class over the next 2 years. I have Tokico HPs all around, and am attempting to bring the rest of the car back to decent condition.
Now for the question: Tires were a big issue during the school, so I was going to upgrade that first, but I want to keep my street tires on my stocker rims (5-lug). Am I better off running T2 rims (16x7) or GXL (15x6) with Falken Azenis Sports, or should I aim for the edge of the STX rules with a 17? This car is all about getting the most out of the car on a budget, and I can probably find the t2 rims at a good price. Tire roll was very apparent, though the crappy street tires can be to blame for most of that, and I was under the impression that the extra inch of rim would help with turn-in. I was also told that with the 17s, the rear wouldn't grip as well rolling on the throttle through the turns.

I've searched this and the wheel/sus sections, but everyone wants to run huge rims and 245+ tires. I just want to make the most of my lil FC no further than STX.

TIA
Pete

 

I have a good set of 17x8's TSW Hockenheims with 235/40/17 Toyo RA1's on them (shaved) for an FC. Perfect offset so that you can rotate them to all corners for better wear. You need to run coilovers (up front at the minimum to clear the rims). They will basically crush any street type tire.

If your car is an N/A this is all the tire you need.

They are very well priced as well and looked great on my FC.

https://www.rx7club.com/showthread.php?t=318541

-Mark

 

I am curious to hear about wider tires not gripping as well upon throttling out of turns. Maybe they meant not turning as well?

Another thing to consider for rear traction issues is the age and mileage on your Sport's limited slip.

 

If I were to do stock rims on a FC I would go with vert rims 15x6.5. You could run the 205/50 r15s, I know it's the same size as what you would be running with the sport rims, but with the verts you drop a bunch of unsprung weight from each corner. I think what they're talking about with the 17 inch rims would be the lack of side wall flex, the shorter stiffer side wall would tend to grip then break away.
And in case people haven't seen this site I believe they are the cheapest place to get the azenis, http://www.vulcantire.com/azenis_t.htm
Let me know if you guys out there have a cheaper supplier for those! Those prices really make me want to run 14s.

 

I agree 100% get some vert riims. They are super light and Spec Miata's run 15" rims too. *hint*hint* You can find used r-compound Toyo's off of the Miata's for about 100-200 for all 4. My friend picked up 4 for $100. He used them for almost 2 seasons including 2 Evolution schools. I would say he got his money worth.

Another plus to running 15's over 17's is you will lower your cars center of gravity. Which is always good.

Oops! You want to run STX class so you have to keep your treadwear over a certain #. Forget what I said about the R-compounds they are totally illegal in STX.

I think Azeenis are legal in that class.

Good Luck!!

 

Who told you that an FC would go into STX? STX is for non sports-car based sedans.
An NA FC would go to STS2.
But that doesn't change the rules much...
You can fit a 225 width tire on a 6.5" rim. I'd go with the vert rims too: less weight, and cheaper tires. So either Azenis if you want to run STS2, or R-compound if you want to run CSP... there is nothing you can do to that car to end up in F-modified.
Good luck

 

Whoa Whoa. STX is for cars with 4 seats only. NO RX-7 falls into that category even the 2+2. You would have to run STS2 to stay in the ST classes. This is not a full national class yet though.

Your best bet is to move into Street Prepared. Almost all of the same modifications are allowed in both classes. The main difference is that SP allows race tires and a few extra mods. You could run Azenis to keep costs lower.

 

While 'vert rims are very light, they're also still pricey.
I ran a 15x7 BBS wheel from a Camry. It wasn't quite as light, but the extra 1/2 inch did well accomodating a 225 tire. Attached are what they look like. I picked them up at a parts yard for $85 for all 4.

www.edgeracing.com is also a very good source for Azenis and lightweight wheels.

 

Thanks for all the replies. I spoke with Greg Smith, the regional exec and solo chair for this area, during the Evo School. He told me STX... I don't think STS2 would be too different. After looking at the CSP and STS2 rules, it would seem better to run stock until I collect enough parts to upgrade into either class.
As far as the traction and rim width, the gentleman I spoke to was running a 330i Performance pkg with rims 18"+. So compared to a 15", I'm sure the break-away is far more abrupt.
Would the vert rims be illegal in stock class? What is the weight difference from the gxl rims? Anybody selling some cheap? I've already installed Tokico HPs, so I'd rather not have to switch to a coil-over in the near future just to fit some tires.
I guess it depends on what class I'm eligible for as to the tire I run. I'd love to play with some R compound tires, but since that is the first upgrade I'm planning, sticking to the Azenis will keep me close enough for the local events to call me stock.
I still have some work to do one the car prior to running more events, so I should have time to find rims and order tires. EdgeRacing's price went up on the azenis to $71!! But they have them in stock where Vulcan ($64) doesn't...

Thanks
Pete

 

I think the vert rims would work for stock class. For the most part I believe that you can run any wheel in stock class so long as the dimensions are the same as the originally equipped wheels. There is also a stock wheel guide in FAQ of the 2nd gen specific board. https://www.rx7club.com/2nd-generation-specific-1986-1992-17/faq-fc-frequently-asked-questions-2nd-generation-rx-7-a-181219/. I run the GXL rims and though I haven't actually weighed them I would guess it to be closer to 18lbs or so. So no matter what you do if you got the vert rims you would be shaving a serious amount of weight in comparison to all the other stock wheels. Check ebay everyonce in a while for the vert rims I've seen them go for around 200 to 300 for pretty complete sets. For the most part you wouldn't need the center caps or the center cap tool so you'll probably be able to find a cheaper set.

 

Vert rims are 6.5 inches wide as opposed to any other 15 for the FC which are only 6. By the letter of the rules, they wouldn't be legal in stock. Of course neither would your motor, so your milage may vary.

 

Doesn't the vert rim count as a stock rim? I dont see why it wouldn't be legal seeing as how it did come on same car.

 

But you couldn't get the vert wheels FACTORY installed on his car when new. That is what makes a wheels stock for a certain car or not.

 

Well if that's the case then wouldn't the T2 rims he mentioned before not be a viable option as well then?

 

The T2 rims were mentioned in regard to running STX or STS2. They'd be fine in that class.

The 'vert rims were questioned for use in Stock.

Another benefit to running the 15's will be shorter overall gearing if you run the 205/50 Azenis.

 

You might ask Mr. Smith to refer to page 94 of the current 2004 SCCA Rule book.

It states: "Vehicles eligible for this category include all coupes/sedans with a minimum of 4 seats, four seatbelts; that are not sports car based...."

RX7s do not fit the above....

 

True but doesn't matter.

In a stock class you may run ANY wheel you wish but that wheel must be of stock size and diameter with an offset within 1/4" of stock (stock being what the car was factory equipped with). It is perfectly legal to run aftermarket wheels in stock as long as these conditions are met.

...and whoever thinks any two seat car can run in STX is smoking something.

 

I over looked this point. You are NOT allowed to up/back date motors in STS/STX and certainly not stock. The only classes for you with open motor rules would be F-Mod or SM2. That loophole was closed after a few people built franken-civics for the Nationals in STS.

Russ

 

I know I never mentioned size because it was already stated that the vert wheels were 6.5" wide compared to 6".

Thanks for helping clarify.