Rexpelagi

I've been to a few autocrosses so far this year but yesterday was the first with the tC. I ended up posting the fastest time in HS for the day (luckily no one there runs on R-comps haha). I did have a few questions for the autocross guys.

First, regarding general tC stuff, I noticed two things while autocrossing the tC.

The first was an issue powering out of corners. I noticed coming out of a few corners on a few runs that the engine didn't seem to rev up, similar to how it might feel if it was being held back by a traction control system. It was only a few times, but it felt like the car was in limp mode for a second before it caught and continued to rev up. It could have just been one of the wheels spinning wildly but to me it didn't quite feel the same? Has anyone experienced this?

The second was something I noticed while braking on the last run. After the finish gate I went to stop and it seemed like there was no where near the stopping force it had on earlier runs. I came inches away from hitting a cone post-finish and throwing away my best run. I'm not sure if I was just coming in a lot hotter? Are the tC's prone to brake fade? (I didn't notice an issue until the finish.) I've heard that some cars have some sort of ice mode with the ABS where it can get flustered and have stopping issues. I was actually on a ride-along in a 350Z and that very thing happened and we ended up flying through the post-finish cones. Does the tC have anything like this?

I also had some questions regarding setup. If I continue autocrossing in the tC I may look into setup changes.

First, what type of negative camber can I get from the front and rear suspension using factory adjustment?

Second, given that HS requires stock wheel sizes but does permit r-comps (and I know this is a general tire fitment question so bare with me), what size tires are some of you guys running? The stockers are 17x7 correct? If that's the case, you could physically fit 245/40's on there, but would that have a rubbing problem on stock suspension? Would it be better to stick with 225/45/17?

Thanks in advance for the help guys!

ack154

iTrader: (7)

Your coming out of corner problem is not having enough gas in the tank. If you're under 1/3 tank or so, it will do that on sharp or long corners. Kind of jerks a little and then catches up to itself.

I don't THINK you should have any issues with brake fade (even though that sounds like what it was)... but if it was a really quick run with a lot of braking, it could be part of it. I'm assuming you're still on OEM brakes? You would definitely notice ABS kicking in though... you'd hear some noises out of it.

Not sure what the OEM adjustment will get you for camber but my guess is probably a degree or two - likely more in the rear than the front.

I think most of us run 225/45 on the OEM wheels... though I'm in ST and can't run R comps.

Rexpelagi

I did have about 1/3 of a tank or less, so that could definitely be it. I didn't realize it was that sensitive.

I didn't really notice the ABS much at all during any of the runs. I am still on OEM pads, but if I decide to use the tC more frequently I will probably change that. Like I said maybe I was just coming in hotter than on the other runs so I didn't leave as much room as I should have to slow down. I was riding the brakes a fair amount while accelerating out of the corners to keep weight on the front end though, so I very well could have just cooked them.

ack154

iTrader: (7)

Ya, I was annoyed the first couple times I was low on gas. I didn't realize I had to have more than what I had in it. I'm definitely prepared now.

Oh ya if you were riding the brake a little, you would definitely get some fade in there. Basically preheated them during the run and full on baked them at the end.

One-Nut_McGee

Likely you wouldn't be able to fit a 245 onto the stock 17x7s. 235 would probably still be pushing it too as you'd be getting that mushroom top effect and the tire would just roll over the rim as you put higher and higher lateral forces on it. Stick to 225 like ack suggested and you should be kosher. If you want more rubber, upgrade to an 8inch width wheel, those will accomodate up to a 245 before you get the mushroom. (It'll move you out of HS into ST (or is it STS if you go to 8"?), but that's your call if you think you can compete in the different class)

On Camber. I run -2 front and -1.75 rear. I've played around with different settings, but the car feels most happy at those settings. I'm lowered around 1.75 inches front and 1.3 inches rear, so these camber settings might not work as well for you if you're still at stock height. Try out a couple of settings (if you can afford to get multiple alignments or know someone.) and see what feels best for you.

As for the brakes, it sounds exactly like you got high temp fade from the symptoms you listed (as well as explaining that you rode the brakes). That's a pretty advanced trick, very cool to see other people doing that! If you're going to continue doing that I'd recommend switching to a different rotor. Pads will help you bite harder, but it sounds more like you were getting into heat problems then bite problems. (Not getting into ABS? Dang, my ABS pumped like a machine gun the times I ran on stock rims, tires, and brakes!) Slotted rotors will help you a bit with length of time you can cook the brakes up like that and still not feel the fade. Better pads might shed heat better too, but that's up to you if you want to spend a little more. (I'd recommend it, but doesn't sound necessary for you yet)

As for the fuel problem, I actually run a full tank. I know it makes me heavier by an order of magnitude, but if you get in a long day with a lot of passes, you can eat a half tank of the fuel easily. I can't stand the cough/surge of low fuel. Unfortunately there aren't any baffled fuel systems that I've found on market right now. Solution is to just run more fuel. How much you run is up to you, but plan for the day. If you think you'll be there all day with lots of runs, just take the weight penalty and fill up entirely.

ack154

iTrader: (7)

Info for ST classes (if you step out of stock class)...

Wheel Width Limits:

ST, STS – 7.5"
STX (AWD) – 8"
STX (2WD) – 9"
STU - unlimited

Tire Size Limits:

ST, STS – 225 mm
STX (AWD), STU (AWD) – 245 mm
STX (2WD) – 265 mm
STU (2WD). – 285 mm

Rexpelagi

Without investing a fair amount of money in suspension among other components I'm not sure how competitive the tC will be outside of HS. I'll probably remain in HS if I can stay competitive there.

HS won't allow wider rims, and anything above 225 throws me out of ST anyway (225 is the max). However DOT R-comps are a go, so I may look into doing that. They are expensive, but they are probably cheaper than trying to setup a car to be competitive in another class.

The only brake modification I can do in HS is to swap out pads, so that may be what I end up doing. Rotors have to maintain the stock setup I believe (as in, you can't go to slotted rotors). I was on the brakes pretty hard but maybe not quite all the way. At my previous two autocrosses I was driving my RX-7 which lacks ABS, so I had to be careful with the brakes. I noticed I was braking earlier than necessary in the tC because of that.

I just started toying with left foot braking but it seems to help out quite a bit, especially on a front wheel drive car. I wasn't sure where I was losing time to my friend (who also uses left-foot braking), but on the last two runs I started using it and it really seemed to make a difference. I'm still no where near as controlled with my left foot though, and the dance between heel-toe and left-foot braking was a little tricky on the one corner entrance where I had to downshift. I basically just used my right foot to brake into the corner and then switched over to use the left foot to settle the car on exit. In the end I dropped over a second from run 4 (no left-foot braking) to run 6 (left-foot braking). It could have just been my times naturally falling as I got better at the course but it definitely seemed to help.

Thanks for the camber suggestion, I didn't realize you could get that much out of the factory setup. My RX-7 can barely get any camber out of the front without camber plates.

ack154

iTrader: (7)

On a regional or national level, the tC isn't competitive in ANY class. In ST it gets spanked by moderately prepped 91 Civics... in HS it can get spanked by any number of things. Mini Coopers... Mazda3? With the right driver anyway...

A not-so-good car with a great driver can beat a great car with a not-so-good driver many times.

It depends on your region. I've won STS/ST the last two years in my region... but that's because there is never any consistent competition... and when there is, either the car or the driver are seriously lacking. I don't really win b/c I'm just THAT good... I win by default. Don't get me wrong, I'll take that... but the tC isn't really the right car to be competitive.

And sadly that is another part of why I will eventually give up the tC. Autocross class and ability will be on my list of things to look for with its replacement.

One-Nut_McGee

I agree with Ack. For the most part, the tC just isn't built to be a top level AutoXer. You can have a LOT of fun and if it's probably a breath of fresh air at your average event (I can't even tell you how many people liked my car or said they were glad to see my out because they'd never seen a tC out before.), but if you get seriously into it, there are better choices to get you to the top more easily.

For a Track (Road Course) car that's a different story. Classing is a little bit difficult as well as finding an event for most people, but even I was surprised at how competent the tC was during open class lapping sessions. For a totally different level of racing, check out Dan Gardner's success. Chris Rado, Kenny Tran, Ptuning, and more are all now fielding road race tCs and I expect to see some pretty interesting results.

It all depends on what you want the car for, but I bought the tC to make it into a track day car and while I wasn't expecting it to be any more than a middle pack car, after seeing what it could do and then seeing what some of the pros are putting down I have high hopes for it to be a front runner once I'm done.

Now I just need to stop going to the track and start using the money to finish buying parts...

scikotictc232

the tc seems better for higher speed courses like TA

Rexpelagi

Well compared to my RX-7 the tC is very competitive. I have a V8 swapped FC RX-7 and it's not even close to being competitive. Since I swapped across manufacturers I'm stuck in XP... with 225F/255R street tires, full weight, and ~300 whp. I'm about 600 lbs overweight, I need tires that are about 60+ mm wider on each corner (R-comps of course), and about 300 more hp to be competitive in XP (assuming anyone actually ran here in XP, which right now means my time gets indexed, which isn't any better haha).

So with all that being said, the tC is very competitive! I understand what you are saying though. This is the first year I've ever autocrossed and it seems like the trick is exactly what you guys said. Know what you want to do with the car and build it to the rules. Pick something that is a known competitor or at least something light and cheap. The RX-7 is a blast but I built the car how I wanted, not how the SCCA rules were structured.

I've been thinking recently about selling the RX-7 and getting something that would be better suited to autocross, but I think I'll wait until I take the RX-7 to a few track days. I think it would be better equipped for that type of race. Until then, I'll be looking to the Scion for autocross I think.

One-Nut_McGee

Ok, I've broken down what you said into it's three most important parts.

Number 1: You own the car of my dreams. I was a kid around the time that the first gen FC rx-7s, the MkIII supras and the like were just coming out and have ALWAYS been in love with the older body styles. With the v-8 swap you literally have the product of many of my youth fantasies about cars.

Number 2: Build the car how you want it (tC and Rx7). I don't care if you go into STX or STU or whatever the totally unlimited class is (Ack, help me out here...the one where you can bring a missle with wheels if you really want). It doesn't matter WHAT class you're in if you enjoy your car and get to do some racing with it. Will you be competitive in the 100% unlimited class if you break all the rules and build your dream car? Not. At. All. But you'll have the car YOU want, and you'll have more fun than the guy who bought a miata he hates just to win with it. I personally am likely to end up in STU when everything gets put together, but I know that and I can pretty well tell you right now that I'll be the slowest in STU every single time. Oh well, who cares? I personally am not interested in the rankings, I'm interested in building my car and then racing it to see how fun it is.

Number 3: Properly size the tires, shave the weight, build it how you want it (and I fantasize it), regulating bodies be damned. As long as it's track legal, you will NEVER sell that car once you take it to the track. You will be so in love with it that you might actually dump/break up with/totally neglect your friends/girlfriend(wife?)/boyfriend/family/pet dog to go race it. Hell, my car isn't even halfway close to being halfway done and I STILL neglect the hell out of my girl. (Sorry babe.)

Once you get the smell of burning brakes, slightly melted rubber, and that beautiful smell of race gas in your nostrils....mmmm...yea, nothing else matters.

ack154

iTrader: (7)

Well the FM (F Modified) cars are usually the little missiles with wheels... but I think AM (A Modified) is usually the "top" class as far as PAX goes.

kuo34

Just like any other sport, autox is prone to gaming (taking advantage of the way rules are written). The tC is definitely not the top gaming platform, but it's not a bad platform to learn on. Starting out with only a couple of mods, I was regularly spanked by stock auto transmissions because I simply sucked (and probably still suck) at performance driving.

New equipment will only take you so far. That being said, if you seem to be well on your way to outdriving your current gear.

One-Nut_McGee

Totally agree with Kuo, and typically I wouldn't suggest dumping a huge sum of money when you're not yet competent enough to push the parts to their limits, but Rexpelagi (the OP) seems to have some experience and some decent racing knowledge.

If you're new...run your car as close to stock as possible for a few times. You'll learn a LOT about your car when it's slow with the mediocre street tires than you will when your car has 4,723,847,289 HP and Triple-R-spec-double-boner Tires on it.

Slowly build up the parts and test run the car as often as you can. You'll grow with the car and be a much better racer overall. If you start with a Viper and no experience you'll be mightily upset when some guy with a Miata and some experience eats your soul on the scoreboard.

senseiturtle

1) +1 on the "tC not being ideal platform for any class." But it's been great for me so far. I finish either 1 or 2 in ST each time, and run somewhere in the second-quarter of PAX results. Better than half, but still beaten by a bunch.

2) If you're serious about maximizing your winning potential, stay with HS. Get a spare set of super light, stock-sized tires on R-comps. That modification alone is simply unbelievable for handling, and nearly equivalent to every other modification I've done (everything allowed in ST).

3) If you're out to have fun and not necessarily win (like me), then do whatever the hell you want! Although the tC isn't the ideal platform, it's taught me an incredible amount about how to set up a car properly.

4) A few months back, people on SCCA forums were _____ing because it was possible to order tC's with the TRD sways already installed AT THE FACTORY. Meaning, if you can find the window sticker saying it was installed at the factory, then it allows the TRD sway in HS. This + Rcomps would likely allow a tC to compete at nationals, but not necessarily win it.

I would check into the validity of the above, but SCCA forum people generally aren't BS'ing around. Prove it before trying it yourself.

5) My ABS goes apes--t on every hard stop during a run. At first, I focused on being smooth... which was great. After mods (namely, Dunlop starspecs) and training, I found I was braking far too early and squeezing throttle way too quickly. I was keeping the car just a little off the edge of full control and not able to recover full grip quickly enough.

Try braking much later and harder, and getting on the power eariler... but much more gradually. It's hard for me to not immediately floor it out of a turn, but my times tell me its worth it.

Rexpelagi

So what is it about the tC that makes the car so uncompetitive? It does seem to make pretty good power for HS, although it is fairly heavy. The wheels allow for decent sized tires too. Does it come down to suspension geometry or something?

I think the only mod I'm really going to do in the near future is a brake upgrade. I will probably get new blank rotors along with either Hawk HP+ or Ferodo DS2500 pads up front and Porterfield R4-S pads in the rear. It seems like several companies (ie, Ferodo and Hawk) don't make rear pads for our cars, at least not of the compounds I wanted.

I also contacted my friend who works at a dealership to see if he can locate the smallest 'OEM' bolts permitted in the manual for the suspension to get more camber out of it. It looks like that according to the rules this is permitted as long as all of the components used are OEM.

senseiturtle

Weight is about 400lbs too heavy.
Weight distribution is way too front-biased.
Stock suspension is far too soft.
No LSD.
2nd gear is way too short for some of the longer spurts.

etc. etc.

--

The problem isn't that the tC is a "bad car," its just that there's several that are far better.

The weight is what really kills it.

Rexpelagi

I just thought I would update this thread, now that I have done a few more autocross events with the tC. I have to say that complaints about the car aside I enjoy driving it a lot. My regular H-Stock competition is a Mazda 3S driver and him and I are fairly close. I have to say that even in stock form I don't really have a problem with the car rotating (at least I don't feel like I do), a bit of trail braking seems to do the trick, but we don't really run any real slow courses. I'm going to finally take off my nearly worn-out all seasons tomorrow and step up to 225/45/17 Star Specs, so that should be fun.

I will probably continue to drive mainly the tC for the remainder of the year, it's nice that no one regularly runs R-comps in HS locally, and hopefully that will continue for the rest of the year.

I will say that it's not quite as fun as my 'other' car, but it's also a lot more competitive.

I can't find any good tC shots, so here are some shameless 'other' car pictures:

Rexpelagi

Well, the first season came and went and I had a lot of fun. I decided that since I haven't been able to sell the RX-7 to fund a dedicated autocross car I'd try my hand with the tC prepped a bit better for H-Stock. I plan to run in a PAX-based class this year, which should give me an idea of how [un]competitive the tC is. ;)

However, these should help...

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