Hey guys, I dont post much but I lurk ALOT. Heres a list of my mods:

Techart Front lip
Techart Sides
Techart Carbon Roof Spoiler
Techart Carbon Mirror inserts
Techart Carbon GT3 Vent
Carbon Rear Cover(forgot company name)
H&r Springs
Gt3 Rear spoiler
Fabspeed intake hose
Fabspeed Maxflo mufflers
Sevas Forged R22

So basically I track on the weekends with my stocks, Im not much of a person to care for power, but I care about the handling. The car tends to get a good amount of understeer at times for some reason. Im gonna try some better tires next, but any suggestions on sway bars, etc. would be great. I am done with exterior mods, just now learning the car and thats why im asking for recommendations, thats all. Thanx in advance guys.

 

Did it understeer with the stock springs??

 

Man, you live in Orlando?? I got to see this thing...Were do you usually roll out too on the weekends...Cars and Coffee? or PCA meets?
I would love to see you car! Let me know...

 

Do you know what your tire pressures are?

 

I have noticed this as well with both the stock suspension and a car with lowering springs. The weight distribution of the 911 makes the front end of the car very very light. To control the understeer you can add some negative camber to the front, but the vast majority of it will be controlled by your steering/throttle inputs. A 911 is a very different car to take in the corners compared to a front or mid engined vehicle. If you get on the throttle hard in a turn (with a stock C2), with the large amount of grip in the rear the vehicle is going to tend to push forward more so than a car with less grip in the rear and a more equally distributed vehicle weight. Granted if you are making a ton of hp and you do the same thing, you will have a lot of power-oversteer. I know in my situation my car is pretty much stock (C2) and for me grip > power level. Sometimes trail braking can be a solution for curing understeer since it distributes the weight to the front tires, but on a rear engine car such as the 911, depending on the speed and degree of the corner that can be a very risky move. I would suggest attending the Porsche driving school or another driving school that specializes in rear engine vehicles as this will help in learning the physics behind why the car responds the way it does in variable situations.

 

The car did it with the stock height, completely stock actuall with michelin pilot sports. I figured it was just the tires, but I guess not.

I think i was in the tires at first and then lowered to 20 something, cant be sure(had the adrenaline pumping when I pulled over to lower the air in the pit haha)

Tripleinboard- awesome info, I have thought about taking the school as I have taking skip barber and done numerous races with scca, and chin motorsports. I guess Ill have to take another school to figure this car out(I used to drive a boxster on the track, then bought a 350z and turbo'd it and tracked that, now im on the 911)

 

By the way, i used to live in orlando but now im in miami for the next couple of years or so. I have pics of the car b/c I actually was sponsored by fabspeed and Sevas forged. I have pics without the wing and gt3 vent, but let me snap a few quick ones with my regular cam and Ill start another thread with pics of the car.

 

None of those mods will fix the understeer. Here are some suggestions and things that have worked for me at the track:

1-Seek an instructor that knows the 997S very well and work on the driving line plus threshold braking and trail braking for your car
2-get -1 degree of camber up front
3-cold tire pressure of around 28-30...38 hot
4-245/40/18 tires up front
5-GT3 control arms to dial in more camber of around -2 up front.

 

I installed the GT3 Cup car lower control arms on my 997S, and with the current shims, it is adjustable from roughly -2.5 to -3.5. I had it on track last week for the first time since the installation, and used maximum camber. I didn't have an alignment, so I'm sure the two sides are not equal after pushing in the strut tops to full negative. But I figure that's okay, the track's not either! It made a noticeable improvement, both in handling and tire wear. I don't think I got any additional outside wear as I was getting before, which is good, because they were about to cord. If you are not crazy with your entry speed, most turns can be managed with a gentle lift if you get too much push under throttle. I'm sure the handling can be further tuned with different bars, but it suits me very well as is. Given the rear weight bias, I expect one has to be careful in trying to dial out understeer, without introducing an oversteer problem, which is much harder for most drivers to handle.