WAC

One of the things I have really learned to enjoy is autocrossing with my local PCA region. It's a great bunch of people, lots of interesting cars, great way to get to drive your car, etc. Last year when I began to think about getting a 997 I really wanted a GT3, even my wife thought I should get one.

Then I saw a new C4S on a trip to San Diego. Then I saw my car on the internet. Suddenly I didn't want a GT3 anymore (well at least I wanted this C4S more).

But I've been wanting to see how well it would run at autox...

It was 30 degrees this morning when we started and only about 45 when we finished so everybody was taking it pretty easy. On summer tires that cold it felt like you were hitting patches of black ice so it made an interesting day. The track was set up 1 mile long with fairly gentle chicanes, 2 decent sized sweepers and an challenging left/right tight accelerating turn in the middle. 2 360's early in the course helped to get a little friction and heat into the tires.

There is a lot of discussion with the C4 about the "pulling" on the front end. Driving on the street its never been an issue. But in doing 360's this morning I figured out that technique is very important. The first couple of runs I apexed too quickly and tried to hold my turns too tight. The car felt like my F250 in 4WD on drive pavement, it sort of crabbed and jerked. When I opened up the turns not only did that stop but the car pulled out of those turns, straightened and lined up for the next chicane much better than my old 996 C2. I believe that the "pulling" of the AWD was a real benefit here.

Once I got used to how the tires were behaving I pushed into corners pretty hard and again I think the added traction really helped me carry speed where the guys in 2WD cars were having to go a little slower.

The steering of the car felt more precise than my old car driving through the esses. But I really couldn't feel any pulling. I realize some think the C2 steering is better but that hasn't been my experience so far.

I had PSM on and it had a little work to do today. You may not be able to throw the back end out on a C4 like you can on a C2 but in conditions like this you can damn sure slide!

I was curious to see how my times would be against a few other cars including a 997 GT3 and a 996 GT3 both driven by good drivers of roughly similar ability to me. I've got basically the same hp as the 996 with the X51 kit, obviously less than the 997. My times were lower than the 996, probably due to experience and slightly higher than the 997 overall (although I did run the lowest time on one run). All three cars get off quickly, by observation of a friend who races my car handled the 360's better, we were pretty even in the chicanes and the 997 GT3 pulls away in the long straight where we're getting up around 100mph but that car can wind it up more and is just faster.

The 997 and I both have PCCB brakes which really help as you come into the 360's and blast through the end gate where you can just carry more speed because you've got the stopping power. It's amazing to blow through the timer gate at 95-100 mph and stop the car with no effort in time to turn into the line up lane when most cars have to let off before the gate.

My car does not sound as cool as either the 997 or 996 GT3 either inside our outside the car when running. Their engines scream and there is not much insulation to hide it. They sound awesome. PSE isn't quite the same but it's better than the other 911 that don't have it - they sort of sound like a Grand Marquis with a sore throat in comparison!

I wasn't the fastest (a 944 Turbo with a very good driver was) but my best times were within a couple of seconds (and I think I know where they are). But I think if improve as a driver my car can keep up with the best hardware out there.

I know that autocross probably has more to do with driving skill than anything else, and there isn't much time separating 914s, Caymans, SCs, etc. but I think this combination of horsepower, brakes and AWD has something to offer. By the way the coolest car today was a Ford GT in Gulf racing livery. But that car is a pig on an autocross track. Looks better siting still...

The bottom line for me is I love my car more than ever now! Not only is it awesome looking - but it's a fast mother too! The GT3 second thoughts are gone.

Now I need some 18 inch track wheels and tires.

Sorry for the long post but I thought that in the debate about X51, PCCB's and AWD it might be interesting.

Tony

cello

Nice write up! For clarification, when you say "opened up the turns " do you mean using a different line than before or are you referring to steering input? Thx.

WAC

Both I guess. I was holding the car (wheel) too tight trying to go in a smaller circle. I kept the same line into the turn, apexed in the same place but when I opened up the circle and made it a little bigger the crabbing stopped, I lined up the 2nd 360 cone set much easier and I was faster. I think what I learned was that a C2 may be able to turn tighter, at least in a circle, without tires chirping or skipping, but I think a C4 may have a better exit. And a little different driving technique in this instance is required.

I hope that explains it better!

cello

Definitely does! Sounds like a little less steering input/correction while in the line and a 'use all the track' mentality would be helpful for the awd sys. Thx.

doctorpcar

I know what you mean by the tire effect on tight turns. I have experienced it on other AWD performance cars, its not unique to the C4 cars. The tighter you turn your wheel while applying throttle, the worse the effect right? It's like jutting that is felt through the steering and the chassis right?

And if I am reading you right you were able to avoid this by simply taking a wider turn right?

If I understand my basic physics this has to do with the circle of traction. There can only be so much that your tires can be doing, they are either applying power or they are steering. I believe it is these types of situations where the two are fighting each other and leaving the driver with a less than perfect feel that requires compensation in a different driving style.

I have driven the C4 a bit but not noticed this quite as much as other cars. I haven't pushed the car though.

Btw, you kept on referring to the 997 vs. your C4S. What do you mean? Do you mean the 997 C2S? Your car in a 997 C4S no?

WAC

Sorry about that, I was referring to the 997 GT3 as opposed to the 996 GT3. Yes my car is a 997 C4S.

Tony

Edgy01

Where did you autocross your car?

WAC

Oklahoma City. We have the use of the Sheriff's training track which lets us set up some great autox configurations. Longer than typical with a huge skidpad area so the setups are always interesting and usually pretty fast for autocross.

Edgy01

That's a lot better surface than the Lloyd Noble parking lot they used to use! (Formerly with the WB region)

doctorpcar

Can you tell me, do you get this jutting effect at slow parking lot speeds? For instance, try driving out of a parking lot and making a right. Your car is facing perpendicular to the road you're about to turn on to. Now begin to drive straight into the road and as you do, turn the wheel to bring you on to the road (turning right) while applying throttle, not a lot, but say up to 15 mph of gas.

Do you get the same problem? I am hoping not, I should think that the car I experienced this on has a much worse problem due to the weight on the front axle, where as the C4 would probably see this in much more extreme circumstances.

Would you say the C4 understeers? I should think it does given what we're talking about, the question is how much so in comparison to the C2?

WAC

No it doesn't do that.

Yes it does understeer but not as much as a C2 (at least the 996 where I have experience). I'll have to drive another autocross or two to feel like I really can answer the question better but I will say that it seemed like it was less necessary to "set" the car (tap the brakes or let off the gas) entering a chicane for example.

Here's why (from Road & Track September 2006)
Like the previous C4, the 2006 model uses a viscous multiple-plate coupling to convey from 5 to 40 percent of the engine's output to the front wheels. This means better traction, especially on slick surfaces. Alas, it also used to mean more understeer. But by increasing grip at the rear of the car, Porsche's engineers were able to increase the stiffness of the rear anti-roll bar while softening the front bar. As a result, the new C4 understeers less, feels sportier and laps the Nürburgring as quickly as the Carrera 2 despite being 121 lb. heavier. Except for a new transmission output shaft and a revised front-axle final drive ratio designed to accommodate differently sized tires, the new C4 drivetrain is unchanged.

Underline mine. I think Walter Rohl actually did it 2 seconds faster but I'm not trying to start any arguments!

I'm looking forward to some warmer weather where I can really push the tires without fear. It will be interesting to see just how well the car "sticks". I'm hoping that it will mean much faster times for me!
It's a GREAT car!

WAC

Dan,

You should come back and visit your roots sometime! I'll bet some of the people you knew then are still around. Of course the SB weather is much better and a run to Solvang for pastry beats the heck out of a drive to Brown's Bakery for donuts!

Tony

Moderato

Thanks for the post. I've owned a couple STI's & BMW's so I have some experience with AWD vs. RWD. As you've said they both need to be driven in different ways in order to be effective. I'm currently driving an 06 M3 ZCP. I've been thinking of getting a Porsche but I just can't decide between a CaymanS vs. 997 C2S or C4S. The problem is that they all have their pros and cons and they are all great cars, so it's a difficult decision. The other problem is sometimes I want AWD and other times RWD. I wish there was an AWD car that gave the benefits of AWD but truely felt like a RWD at the same time. Maybe the C4S is the closest to this ideal right now. I haven't driven an R8 but I do wonder how it compares to the C4S. I've seen some videos of comparisions but you can't really base a decision on that.