Got a track related question? I'll try to answer.

[troek]

i belive @CSG Mike has posted that its better to gain camber at the hub/knuckle, as its best to keep strut angle changes to a minimum. although you usualy cant gain enough camber there, in a safe/recomended manner.

[dradernh]

Originally Posted by troek

...on the slow, almost 1st gear hairpins i was getting severe understeer...what would some driving techniques be to fix this?

You could always try left-foot braking. Gentle left-foot braking.

[gramicci101]

Originally Posted by dradernh

You could always try left-foot braking. Gentle left-foot braking.

Key word: gentle. The first few times you try this you will brake check yourself pretty hard. Learn on a straight line before you try it in a corner.

[kavanagh]

Originally Posted by troek

i belive @CSG Mike has posted that its better to gain camber at the hub/knuckle, as its best to keep strut angle changes to a minimum. although you usualy cant gain enough camber there, in a safe/recomended manner.

That's what I was thinking as well. Is slotting the knuckle holes a bad idea? I see people talk about slotting, and I assume they mean at the top of the strut tower.

[gramicci101]

Originally Posted by kavanagh

That's what I was thinking as well. Is slotting the knuckle holes a bad idea? I see people talk about slotting, and I assume they mean at the top of the strut tower.

They expand the top of the two holes that mount to the knuckle. That way they can push the hub back without changing the strut angle. Some struts or coilovers come with that hole slotted already, like the RCE T2.

[kavanagh]

Thanks! And I think that's a zero point mod in NASA.

[unsurety]

Do you guys "heat cycle" your tires before mounting them? Discount Tire offers a service for it. I just found out about this... not sure if legit. Going along with this, what do you recommend for tire longevity for the track? Warm up lap, cooldown lap...?

http://www.discounttiredirect.com/di...HeatCycling.do

[CSG Mike]

Originally Posted by kavanagh

That brings up a good question for me.

Is it 'better' in this car to gain camber at the knuckles or plates? I have one crash bolt only at this point in the top knuckle holes, and I'm deciding on what path to take for more negative front camber.

There's pros and cons to both, but safe to say that unless you're at a VERY high budget, a camber plate is better. The "superior" method requires basically customizing everything.

[dradernh]

Originally Posted by unsurety

Do you guys "heat cycle" your tires before mounting them? Discount Tire offers a service for it. I just found out about this... not sure if legit. Going along with this, what do you recommend for tire longevity for the track? Warm up lap, cooldown lap...?

http://www.discounttiredirect.com/di...HeatCycling.do

Not for "tweener" tires like NT01s or R888s.

But for R6s, R1s, etc. I do it simply because I'm too lazy to do my own cycle & scrub. I'm willing to give up the scrub for the convenience of not having to run them for a few laps and then set them aside. I did this even when I had 10 sets of tires and wheels and took 7 of them to the track with me. For $60, I found it to be a no-brainer.

More on DOT-R compound tire ownership here, including some overlap with the Discount Tire link above:

http://www.tirerack.com/images/pdf/warranty/HOOSIER.pdf
http://www.tirerack.com/tires/tirete....jsp?techid=66
http://www.tirerack.com/tires/tirete...jsp?techid=221

[dradernh]

Originally Posted by gramicci101

Key word: gentle. The first few times you try this you will brake check yourself pretty hard. Learn on a straight line before you try it in a corner.

Good advice. In the one spot where I use it, it's just a brief brush of the pedal, though that won't necessarily be the case for other cars, turns, or drivers.

Didn't someone suggest that when Michael Schumacher was demonstrating superior speed through certain corners that it was due to his left-foot braking technique?

Assuming it's legal, you can practice this on the street to get yourself used to it. Or, just go karting a few times, where you'll be forced to develop some skill at it.

[gramicci101]

Originally Posted by dradernh

Didn't someone suggest that when Michael Schumacher was demonstrating superior speed through certain corners that it was due to his left-foot braking technique?

To be fair, he had a paddle shift transmission, so he could brake all the way into corners with his left foot. I think all F1 drivers left foot brake. For those of us with a third pedal, we're kind of limited to short braking zones that don't involve a downshift, or we start to look like Fred Astaire. The throttle-brake-throttle transition is much quicker though.

[kavanagh]

Originally Posted by gramicci101

To be fair, he had a paddle shift transmission, so he could brake all the way into corners with his left foot. I think all F1 drivers left foot brake. For those of us with a third pedal, we're kind of limited to short braking zones that don't involve a downshift, or we start to look like Fred Astaire. The throttle-brake-throttle transition is much quicker though.

Elegant heel/toe or toe/toe technique can accomplish the same. Instead of jabbing the throttle to get a blip for a shift, be smooth.

Says the guy that now drives with paddles.

FWIW I still cover both with one foot especially under hard braking on the street. It's an old habit that refuses to go away.

[daiheadjai]

Originally Posted by daiheadjai

Not sure if this is the right place for this:

I took my car to the track for the first time.
Unfortunately, I understeered in one of the tighter corners so that my front left wheel went over the curb (the red/white ones) in an area where the grass was worn away/there was a slight dip from other cars going in.

Visually, I could see no damage, but I did go over it with a bang.

Leaving the track, I noticed a slight vibration in the steering wheel when I get over 120km/h, and the vibration becomes more constant when I take right hand curves.

Does this sound like an alignment issue, or is there something more serious I should check for?

Many thanks!

Update:
Brought the car to the Subaru dealership for them to check.
Here's what they came back with:

Their conclusion after taking the car on the highway is that it is due to an exhaust leak, because my of my GReddy axle back is not OEM and "not a proper fit" (despite it being designed for this car)
They also told me because I modified my car, this would void my warranty.

Pretty sure I won't be getting my cars serviced from that dealer again, given that the extent of my mods is an intake and exhaust.

Also, I hate to be "that guy" but I kinda doubt this conclusion, because I can't quite see how an exhaust leak would only happen at 75kph and 120kph, and have a tendency to be louder/detectable through the steering wheel only when I turn to the right hand side.

Anyone have experience with this sort of thing who can chime in and let me know if I should bring it to another shop for a second opinion?

Thanks!

[GotMunchies?]

Originally Posted by daiheadjai

Update:
Brought the car to the Subaru dealership for them to check.
Here's what they came back with:

Their conclusion after taking the car on the highway is that it is due to an exhaust leak, because my of my GReddy axle back is not OEM and "not a proper fit" (despite it being designed for this car)
They also told me because I modified my car, this would void my warranty.

Pretty sure I won't be getting my cars serviced from that dealer again, given that the extent of my mods is an intake and exhaust.

Also, I hate to be "that guy" but I kinda doubt this conclusion, because I can't quite see how an exhaust leak would only happen at 75kph and 120kph, and have a tendency to be louder/detectable through the steering wheel only when I turn to the right hand side.

Anyone have experience with this sort of thing who can chime in and let me know if I should bring it to another shop for a second opinion?

Thanks!

An exhaust leak won't cause a front end vibration, that dealership was looking for an excuse to not work on your car.

Did you lock up the brakes before going off?

Take another look at your front left wheel, brake rotor, and all the suspension components associated with it. Get your car's jack out, take that wheel off and take a closer look at everything. Give everything a quick wiggle to see if anything got knocked loose or is bent.

Take a look at your wheel - are there any wheel weights still attached? Perhaps there is a blank spot where they USED to be attached?
If it was really muddy, mud can get stuck in some surprising places and cause vibrations.

Does the car pull in any direction?