SCCA Solo C Street Discussion

[bimmer635csi]

So our local club is having an autocross on a road course. From what I understand, it is the full course with some slaloms built into the straights to keep the speeds down.


Do I need to do anything different? I'm guessing not since the speeds are low, but maybe some brake pads and brake fluid change just for ha-ha's?

[renfield90]

Originally Posted by bimmer635csi

So our local club is having an autocross on a road course. From what I understand, it is the full course with some slaloms built into the straights to keep the speeds down.


Do I need to do anything different? I'm guessing not since the speeds are low, but maybe some brake pads and brake fluid change just for ha-ha's?

You'll be fine. Where road courses get you in trouble is repeated brake zones lap after lap for 20 minutes at a stretch.

You probably have some rule saying 4 wheels off and you're done for the day, but if you let the fear of that limit your aggression you will be slow. That said you will want to look at runoff areas and decide what your risk tolerance is.

[qoncept]

Originally Posted by bimmer635csi

So our local club is having an autocross on a road course. From what I understand, it is the full course with some slaloms built into the straights to keep the speeds down.


Do I need to do anything different? I'm guessing not since the speeds are low, but maybe some brake pads and brake fluid change just for ha-ha's?

I've done events at Talladega Gran Prix Raceway and Hawkeye Downs (a 1/2 mile oval). If it's an SCCA event the same rules apply (target speeds, etc). If there are any walls you'll have added restrictions for the course design and they'll delay the event if there's rain.

My general opinion is that it's really not much different. The speeds have been marginally higher at those events but you can go in expecting a normal SCCA autox. I went to a Corvette club event at the oval and they set the course up fast as hell.

[AustinTX]

Chris - you won't have any problems. That is, unless it's raining and/or you go off. And those problems won't be related to pads/fluid...

[Cueman]

Is there a consensus tire size? I just picked up an FRS and a ditched my ESP WRX.

Sounds like most are on 17's with 235/40's all around... but there is occasional mention of 245's.

Anyone taking advantage of the ability to change diameter?

[bimmer635csi]

Originally Posted by Cueman

Is there a consensus tire size? I just picked up an FRS and a ditched my ESP WRX.

Sounds like most are on 17's with 235/40's all around... but there is occasional mention of 245's.

Anyone taking advantage of the ability to change diameter?

Consensus is a dangerous word around here. Mostly because everyone likes their cars to handle (and sometimes look) different. And even if you found a group of people that said their aim was to have a "neutral car", I bet there would be a scale of moderately loose to moderately tight cars in the supposed "neutral car" group.






You'd probably get more useful information by asking specific questions. As an example, the 235/40 you spoke of seems to be better for short courses. Therefore, a better question might be "Is the 235/40/17 tire useful for courses with long sweeping layouts?" ... to which the answer would be "Not usually because you'll run out of gear and have to shift into 3rd"

[AustinTX]

Seems that 225/235/245's all work. 225 and 235 with a stiff sidewall still provide good transient performance. 245 (at least on my car) suffers a bit on transients, but seems to work well for sweepers. The difference in gearing between the available tire sizes is too small to worry about, IMO.

[Biggins]

No consensus... I have 215/45, 225/45, and 235/45 from three different brands. People are competitive on each of these sizes and brands as well as 235/40 and 245/40. I'm back at the drawing board for next year, but my car feels best on 225/45. It has been faster on 235/45 and also on 215/45 though. Maybe I'll try 235/40, but I have 5-6 months to think about what I want to try next or see what else gets released...

[Cueman]

Thanks all. My inclination was to order 245/40 17's... but I think I'll start with 225/45.

I also noted that 245/45 16 (a Bridgestone only size) has a recommended rim width starting at 7.5" so it's less of a squeeze than the 17" 235's. Might give that a shot if I can find some light 16" wheels.

[vroom4]

They will feel spongy compared to a 17" wheel.

[7thgear]

one thing no one is talking about is going up to 18" wheels...


something I'm considering testing for next year


assuming I can even find an 18x7 5X100 wheel :o

[AustinTX]

RE: potential class imbalance

I certainly am not taking sides regarding this, as I own one of the cars in question and feel it's already been discussed enough by car owners to the point that nobody wants to hear opinions of twin drivers anymore. Our reputation has taken a hit because of this.

I believe my performance at nationals was hindered by 3 things - my own driving (mostly day 1), BRZ spring rates, and tires with poor transitional performance (too wide with soft sidewalls). The tire and spring concerns are a rather small thing compared to me not nailing a couple runs, but they definitely contributed to car comfort and as such have at least some of the blame for lack of pace. Not sure how much time differential is there, but the fastest twin time from each day would have placed 6th - still over 2 seconds back.

Rant - There were past nationals trophy winners scattered all through CS, so I'm not really buying that the only talent in the class was the top 3 drivers. Excluding the time of the top 2 drivers, it was actually a pretty close battle. Are Stuart, Fenter, and McCelvey better drivers on average than the rest of the field - almost certainly. Could they have gone faster - most likely. Were the twins represented well at nats - I'd like to think so, but I know I left some time out there. Probably not 2 seconds, but maybe around 1. That brings the parity question to a point where a course design can easily shift the balance of power around. This was a rebuilding year for me, so next year, it's on

[Kido1986]

Originally Posted by 7thgear

one thing no one is talking about is going up to 18" wheels...


something I'm considering testing for next year


assuming I can even find an 18x7 5X100 wheel :o

A lot of research into this found one cheapo wheel in that size. If I can find my post on RRAX about it, I'll let you know. Outside of that, I found one JDM-only wheel that works and is very rare. The Volk CE28 Eco Drive. It was a Toyota dealer option for Prii (Priuses?) in Japanland. I had a hell of a time finding a pair. Kept finding 1 single on Ebay but no luck on a matching one

I considered it but found Im barely hitting the limiter at National events, timewise. The extra time accelerating wasn't worth it. Someone did the math for me based on Dixie where I RODE the limiter and showed in an ideal world, with instant acceleration from 59.2 to 62mph, I would net .1 second on that 45 second course. Acceleration hit all over the course wasn't worth it (maybe if I had enough power to cause wheel spin on acceleration but not in this car)

[xwd]

You definitely don't want to raise the gearing. It's too bad Subaru didn't bless us with a 7800 or 8000RPM redline.

As for other cars and moving them, I guarantee someone is going to propose moving the 370Z to BS. I don't think it's just twin drivers who would write in to move them either, it's going to be everyone but the 370Z drivers. I also don't think that car is uncompetitive in the current BS at all which will go a long way to it getting moved, it's not like it's being put out to pasture to die. The Harvey/Fenter MX5 is very well prepped with $$$ Penskes that Chris knows how to setup (he revalves them himself). No one else has been able to make that car work.