Track report: RX-8 at Sears Point
 

Well, I made it to Sears Point (sorry, Infineon Raceway) yesterday in my new RX-8. After a day on track, I'm very pleased with the way this car performs.

Some background: I've been participating in open track events for almost 5 years, up until now in a 96 Mustang Cobra. As it sits now, the car has a full Griggs Racing suspension on it (the Mustang platform is so bad you have to re-engineer the entire suspension to make it not suck). However, it's not a car I want to drive every day, and it's not holding up well to track abuse.

My RX-8 is a base model. I've had it for about 6 weeks and it had about 2000 miles on it when I started yesterday. The only mods so far are the MP3 CD player and Mazdaspeed brake pads.

This is a very precise car. I was able to easily put the car right where I wanted it. Before I basically aimed for a point and if I got close I was happy. Now, I put the wheels right where I want them. It makes the car easy to drive fast.

The car has a bit of lift-throttle oversteer. This took me by surprise a couple times, as I'm used to modulating the throttle to get the car to go where I want. I guess I backed off too abruptly, as the tail started to come around. I'm now very careful with the throttle. On the other hand, the car is very easy to catch once it starts getting out of shape. I basically put in a little opposite lock, didn't lift, and waited for it to settle down.

There is a bit of push, but it's not too bad. There's also quite a bit of body roll, but no more than I'm used to in the top-heavy Mustang. Some stiffer sway bars are probably in order.

The brakes held up well. I was a little concerned since I could fade street pads in a couple laps with the Mustang. The Mazdaspeed pads dusted like mad, but they did not fade. However, as I was still learning how to drive this car, I wasn't using the brakes to their fullest capacity most of the time. I have a feeling I'll need to find a more aggressive compound later, especially if I step up to race tires.

One thing I like is the lack of tire wear. I was really beating on the tires during the last session of the day, and they got hot and the grip went away. When I got back into the paddock though, they didn't look bad at all. I guess I shouldn't be too surprised, as this car is relatively light and has a proper suspension design.

The rotary ran like a top all day long. It burned about half a quart of oil over four 20-minute sessions, which is about half of what the 4.6 would consume. The water temp gauge didn't budge all day. The 8500RPM buzzer is completely useless on track, and I bounced it off the rev limiter a few times. I had a couple mis-shifts, due to me getting thrown around in my seat. I also have a problem with hitting the windshield wiper stalk when I take my right hand off the wheel to shift.

I don't miss the 80HP that this car gives up to the Mustang. I'm about as fast in the RX-8 since I can carry more speed over much of the track.

Overall, I'm extremely happy with this car. Right out of the box it's damn near as fast as my modified Mustang. It's a lot of fun to drive at the track, and when the day's over I can turn on the CD player and A/C and drive home in comfort.

good to hear

Really? Do you have the Dunlops or Bridgstones, probably Dunlops? I enjoyed the detail in your post, but was thrown with your comment above. My car has the Bridgestones and they wear by merely looking at them.

What is an open track event?
 

This may have been covered in other threads, but I would be interested in what an open track event is. I live only about an hour from Sears Point and would love to be able to do some laps there. How much does it cost? Can anyone do it? Do you need to have a racing license or any special qualifications?

What kind of lap times did you pull at Sears?

did you run the full track or with the bypass?

great report!

james

I have the Bridgestones. I did have some heat cycled rubber on the tread, but it wasn't a lot. There was no chunking or other overt damage. Keep in mind that my previous experience with tire wear is with a nose-heavy, 3400lb beast of a car, so it's possible that what I consider minor wear is a little different from everyone else.

We ran the full course. I've only run the NASCAR chute once, and while it's fun, the full course with the Carousel and a proper Turn 7 is better. I was following close behind a Miata who was running 2:05-2:06 lap times, and he was holding me up a bit, so I'd say somewhere around 2:04-2:05. Next time I'll have my Hot Lap timer and hopefully a camera set up.

More info on HPDE/open track events can be found at NASA's web site. There are other organizations that run events, but NASA is the one I usually go with. All you need is a car in good shape, a driver's license, and a helmet. Cost is usually something like $150 for one day or $250 for two days at Sears Point or Thunderhill. Laguna Seca is always more expensive.

I'd suggest getting a CG-Lock to keep your butt planted. $35 bucks to not miss shifts again would be worth it to me...

Make sure you order it directly from CG-Lock, not one of the resellers. Why? Because when you order it, you need to tell them you need one with CURVED grips. I'm probably the only person in an RX-8 with a CG-Lock, but I'm definately sold on how great they are.

No, I don't get anything for recommending them. But, its one of the best purchases I've made for autocrossing, thats for sure.

Brian

Get yourself some RB swaybars... and don't go cheap, get the endlinks also. I am amazed at how much of a difference it makes! I can get the car completely sideways with 2 people in the car, and there is almost zero roll.

Matt-man,

Glad to hear that you have you fun with the 8. I've 6 track days on my 8 already and its not even 5000 miles yet ;-)

>The only mods so far are the MP3 CD player and Mazdaspeed brake pads.
I used the Mazdaspeed pads too. And they're great albeit a bit pricey.

>This is a very precise car. I was able to easily put the car right where I >wanted it ......
I agree and I found that I can generally take a tighter track-out line than my old E36 325is. May be possibly due to the lower inertia?

>The car has a bit of lift-throttle oversteer.......
That's what a good handling car should be. You can litereally throttle steer the car in tight curve situation like at the bottom half of the carousel at Summit Point :-) Of course you have to modulate that gas pedal not to cause the tail end to snap around.

>There is a bit of push, but it's not too bad. There's also quite a bit of body
>roll........
As expected, the stock suspension is not quite ready for track purpose. I personally found it to softy and leaning too much.

>The brakes held up well.......
The brake has tremendous stopping power and the Mazdaspeed doesn't fade at all. But the biggest gripe I have is the instability of the tail end under heavy braking situation!! I've already talked about that in another thread https://www.rx8club.com/showthread.p...ighlight=drama
And because of that, I have to back off and apply the brake much sooner than I would like. And that translate to lose of time on track! As I said before I have never experienced anything this bad in my older bimmer at track condition. And I still need to sort out exactly what's causing the problem :-(

>I was really beating on the tires during the last session of the day, and they >got hot and the grip went away.
Same here. Guess its time to upgrade to better tires ;-) Friends have been using the Kuhmo MX and they all highly recommend it.

>It burned about half a quart of oil over four 20-minute sessions
Just about right. Luckily oil is cheap ;-)

>The 8500RPM buzzer is completely useless on track, and I bounced it off >the rev limiter a few times.
Me too. And that's what the rev limiter are for right.

>I don't miss the 80HP that this car gives up to the Mustang........
Well, more hp and torque are always welcome. I've many times that people giving me the pass signals but I just don't have the pull to make the over-takes!
I can outbrake and out handle many cars on the track, but what I've seen again and agin was the guy in front just walking away from me gradually once we hit the straight away. And that's a real bummer!!

>and when the day's over I can turn on the CD player and A/C and drive >home in comfort.
On some rare occasions, I even turned on the AC as soon as we were on the cool down lap.

I did notice a little squirrelly behavior under hard braking when I finally got to the point where I was using most of the braking potential. I'll have to keep an eye on that.

I'm signed up for another event in October so I may take the opportunity to throw a set of sway bars on there and see what happens. I just threw my race tire/wheel fund at another toy so that'll have to wait. :)

Thanks for the recommendation on teh CG-lock, I definitely need one since I have no plans to put harnesses in the car.

Same here I have the MazdaSpeed pad and I am not using the full potential of the pads at all. Hmm... get me to the track next time and i will bit the hell out of it

Nice report. :)

I hope to get my skinny butt on to a track, if I can find one that isn't 1/4 mile.

So does anyone have an idea as to what is causing the rear end to get light under braking? Do people with the MS springs/shocks have this problem? Too light of spring rate in the front? Too much bias to the rear brakes? Bad braking geometry in the rear? I'm going to try and get the '8 into track shape by next summer and figure the braking issue is the first I want to tackle. And all the better if I can kill two birds (roll and braking = springs and shocks?) in one shot.

Great post, I'm glad I checked this one out.

>Too much bias to the rear brakes?
That's most likely to be one of the leading causes of the problem. But fixing it would required changing the proportioning valve of the brake cyclinders. That would be getting a bit too technical and risky!
In the mean time, I'll have my car back to the dealers for an alignment check next week. I doubt that would fix the problem but that's just about the only thing that the dealer can do!

you can also install a proportioning valve to limit rear brake bias. however i dont know how this would work with the 8's super advanced (i.e. ABS braking system). i switched from a single MC to a dual master with a balance bar in one of my race cars- perfect adjustability. its not hard in a non-electronic car. dont know about the 8 though.

shouldnt the ABS prevent premature rear lock up? ive used the brakes at threshhold from over 110 mph several times and the car is more stable and confident than any car i have driven or raced.

my ITS race car has a welded rear diff, so if one rear wheel locks, they both lock. now THATS exciting!

hope you get this problem settled.

james

>ive used the brakes at threshhold from over 110 mph several times and >the car is more stable
Seems like its slightly different from car to car!!

>Seems like its slightly different from car to car!!

perhaps, but also track use is different as the brakes and tires get very very hot. it might be that under these conditions there develops more rear bias- for example if the fronts get hot enough to fade slightly.

you could test this cheaply by adding brake cooling ducts to the fronts. (which is a good idea anyway).

james

Well, it doesn't feel to me like the rear tires are anywhere near lockup. I usually get the fronts pretty close, if not into ABS accidentally.

You could also test the bias theory by changing aroudn pad compositions front/rear. I suppose I could put the factory pads on the back and see what happens, though this hasn't really been that big a problem for me so far.