pete13

Does anyone know of a reference (book or internet) that describes the handling characteristics of a c4 as well as driving techniques, etc? What can you all tell me about driving a c4, how it relates to a c2, front engine car, and so forth? For instance, does the c4 hit you with throttle liftoff oversteer like the c2? Can you steer with the throttle while applying opposite lock with a c4?

Thanks for the help guys!

Van

Only with the PSM off.

redridge

isnt this the case for a c2 as well?

The c4 was really designed for stability rather than an awd function. The c4 has a heavier steering and has more feedback on the steering wheel since it is also attached to the front wheels. You can throttle steer the car, but when you push the car beyond its threshold (by stepping on the brakes PSM will intervene (thats fine, if your on the brakes, you prob need the help anyway). The c4 has so much grip that its very difficult to break the tire free. The c4 has a maximum ratio of 40f/60r of power between the front and rear. More and more professional are being sold to the c4... Walter Rhol (Porsche Test driver) prefers the c4 of the c2 variant.

Van

The C4 came standard with PSM - I understand that it was an option on the C2s... So it could be the case for a C2 as well.

DCP

This doesn't answer much of your question, but it is something.

http://www.youtube.com/watch?v=RYAkYe1Zylw

This clip omits the bit at the end of the evaluation where they agree they prefer the driving characteristics the C2.

rountreed

Yet the C4 was fastest by 1/2 sec.

DCP

Exactly. The tight course put a premium on getting power to the road accelerating out of the corners, more than making up the weight penalty. I would think that on a course with fewer tight turns the C2 might be faster than the C4 simply because it weighs less.

rountreed

So you agree the C4 is better.
Anyway both are great cars!

DCP

Since I have a C2, of course not! They are both wonderful cars.

Dharn55

In almost all the reviews and tests I have seen the C4 consistently beats the C2 in Lap times, particularly in the hands of a less experienced driver. And here in the hands of an experienced driver it still bests the C2. However, many prefer the feel of the C2, more traditional. Once your out in the wet or snow there is no comparison, the C4 will walk away from a C2.

skiracer

For driving in the Colorado snow country, C4 w/ PSM is the only way to go! If I lived in Dallas or Atlanta it might be a different story.

smackboy1

I've driven both. To quite frank, for the vast majority of the time, a C2 and C4 drive and handle almost identically, especially in the dry. The C4 is noticeably grippier when it's slippery. The C4 viscous coupling center diff was designed to give the AWD a rear wheel bias, the rear tires are so big and grippy, and the extra weight of the FWD is relatively small compared to the engine. Both C2 and C4 can exhibit trailing throttle oversteer, trailing brake oversteer, corner entry understeer etc..

RAC

+1, but even if i lived down south I would still have a 4.

DallasC4S

Pete:

Great question! I've been trying to get an ansewer to that myself. I have attended several DE's, but have yet to have an instructor that understood the dynamics of an AWD car. I even enrolled for a Lamborghini driving event two weeks ago hoping that their instructors would be more familiar with AWD. Unfortunately, they had local instructors that didn't specialize in Lambos.

My experience in my car is that I am able to get on the gas much earlier exiting the turns than the RWD cars. I can really feel the car pulling me out of the corner and can usually get a 1-2 car length jump on other cars. The downside is that the car tends to understeer through the turns. However, it is very controlled throughout the entire turn. As soon as I back off the throttle it hooks back up. I don't have any problem keeping up with similar powered RWD cars.

Hopefully more people with AWD track experience will chime in.

springgeyser

Speaking from DEs/AX only. My C4 is setup pretty neutral, if it understeer (excluding slow corners) it is probably driver error on my part. With PSM off, it drives just like a C2. If I had to buy another Pcar, it would still be a 911 awd variant.