RodeoFlyer

Huh????????

Please explain how you think that spring change will help considering you don't know the rate of the Vogtlands or his current ones.

.boB

Spend some time reading and understanding this write up.

http://www.teamscr.com/sway.htm

Texotic

i might be working a corner for the October 4th-5th Driver's Edge event and will probably work a corner for the Viper Days on the weekend of the 11th. let me know next time you go, i'm going to try to go to the TWS Motorsport Performance Driving School in december.

Sleeper_08

Must be nice to live somewhere you can go to a track day in December!

Texotic

i guess. i'd rather go to the track in the summer and be somewhere i can go snow skiing in the winter, but oh well. at least i don't have to shovel snow

Argonaut

A few observations on my experience with understeer:

I'm running Nitto NT01s (275/40/17) with stock sways, Camber plates (set to -2), toe set to zero, Eibach Pro and Tokico D-Specs. The camber plates are maxed.

A couple months ago, when I was running Falken RT-615s, the understeer was very slight and hard to notice unless really pushing it.

With the switch to Nittos, it became a little more pronounced. Not bad but easier to feel. I've played with the tire pressures and damper settings and its gotten better but its still there more than I'd like.

On dry pavement, for my ability right now, I can live with it. But on wet....the car is a plow in the corners, no front end grip at all. In fact, on a wet skid pad it was kind of hard to break the rear end loose before the front.

So, I'm looking for a way to adjust this also. According to Rodeo's comments above I should look to the front end first. I could try camber bolts to increase the negative camber but that may cause tire wear issues in day to day driving which Im not real keen on. So I think the only other thing is adjustable end links. I'm not clear on exactly what these do. I understand that the end link goes from the strut to the "lever" of the sway and that adjusting the length of the end link can adjust the "pre-load" on the bar. But how does that affect understeer? It doesn't increase or decrease the lever arm of the sway (or does it?) so how does it affect the "spring rate" of the sway which is what would increase or decrease the tendancy to understeer. In reading on corner-carvers it sounded to me like the primary purpose of adjustable end links is to aid in corner weighting the car. Anyone offer help?

Taking a look at the rear end, I think my best option is an adjustable rear sway. I understand what this does (I think), I can increase the spring rate by shortening the lever arm of the sway and thus bring the overall handling more into balance.

Comments?

Sam Strano

Here we go....

Maybe becaue Jim has a set of the mentioned springs on his car, and it's working well. Maybe because we know he's on stock springs? At least I do because he's a customer of mine. Also note the car is on Koni's and has some camber, and that's about it. It's also on street tires. And if you read Argonaut's post you will quickly realize that different tires (even if all 4 are the same size) will effect the balance of the car.

Now, I'm sure Wayne (that's the OP's real name) has felt I'm driving him nuts. He's called to buy springs and bars are various times. But I had concerns about whether or not he'd explored his in place adjustments and encouraged him to play with the damping. I'm not sure if he has or not, but hopefully so.

At this point he could consider either bars or springs. Both will change the balance of the car, because both effect wheel rate. Do you want the car lower? You can't get a lower Cg with bars, but you do with springs.

Springs are cheaper, and because the car has pretty damned good bars on it stock (34/20) I tend to start with springs because I feel it's a bigger gain on these cars than say on a Camaro which has a only a 30 or 32mm front bar. I don't think adding a rear bar is a wise idea with a stock front. I run a Shelby GT, it has 35/22 bars and springs. I run the front bar in the middle position (stiffer than just 35, and obviously stiffer than a 34). Adding a rear will increase the rear stiffness too much realtive to the front. And bear in mind this is for autox where balance is even more critical because the turns are tighter and there are more of them. A car can easily get away with being tighter on a road course due to the larger radius corners and the fact there are fewer of them. What's more, you don't want a car that's at all loose at speed. That's asking for an accident.

S197steve

Off topic hijack... sorry:-)


I've done 8 (I think) trackdays there on my motorcycle with LoneStar Trackdays. We always ran the 2.9 mile course.

I would really like to get out there in a car, but as seasoned as I am with motorbikes I'm equally as green with car trackdays!

Do you have any advice as to how to get out to the track? My GT is my daily driver so I'm a bit hesitant especially because I'm aware of what sort of carnage an off track excursion can have on a bike!

BTW, what sort of times are good for cars there at TWS for the 2.9 mile loop? Anything under 2:00 is pretty fast on a sportbike and anything under 1:50 is fantastic. On my CBR600 I was running between 1:59 - 2:02 consistently.

houstonnw

Since I started the thread I guess I can continue the threadjack.

All a beginner needs in these cars is fresh brake fluid and make sure you have more than 50% of your brake pads. I did over 10 track days at TWS with stock brake pads and Pirelli all-seasons. However, with your experience, you might get into brake fade. Here's a good thread on track pads and fluid.

Interesting, the car times are similar: 2:00 is fast and 1:50 is really fast. I'm stuck up at around 2:10.

Unless you try to save it, going off track isn't so bad in a car. Both feet in and don't try to save it. Typically you'll just end up with a car full of dirt.

Sleeper_08

I agree but it does depend on which track your on. So far I've spun once at Dunnville and once in the wet at the Mosport Driver Development Track (DDT). In both cases it was drive to the pits, quick visual inspection and back on. If that had been the Mosport GP circuit the results can be quite different as more than a few Porsche and Ferrari owners will confirm.

FWIW I figure that anyone who drives a bike on a race track has to be crazy