CAA

Here is what may be a dumb question but I was hoping someone might be able to help. I have a C4S with the 18" Turbo twists riding on Pzeros (n type I think???). Anyway, after leaving my fiancees place the other night it was raining, moderately, and I was at a point where I had to make a U-turn and accelerate rather quickly as opposing traffic was approaching at about 45 MPH about 1/4 mile away. Make sense? So after turning the corner I get on it and the car just starts hopping and would not bite. If I have all wheel drive why the hell does this happen - I was pissed. My last 993 was a "95 C4 (narrow body) and it never did this. It was riding on 17s however. At the risk of sounding dumb - does anyone have an explanation or similar experience??? Thx. <img src="graemlins/cussing.gif" border="0" alt="[grrrrrrr]" />

Matt Vaughan

A couple things come to mind... Your tires may have significant wear on them, and need to be replaced, or that could have been a particularly slick part of the road. The road could have had oil, dirt, grease, any number of things. Also, the type of road could also be a determining factor.

CAA

Yeah - thought of that. However, I should have added that all 4 tires are about 1,500 miles old.....

KC993

On my way home everyday, there is a simple 90' right turn to merge into traffic. I ALWAYS put my foot down as my way of "cleaning" the engine. Anyway, when the road were wet, I have gotten tires hop, 4 wheels drift, and sometimes the green "ABD" light came on. So, my explaination is that maybe you just happened to NOT get traction to the road this time.

ZCAT3

Apparently the "hopping" phenomenon is not too unusual with the AWD 911s. I have heard several 993TT owners report that all 4 wheels hop if you do an agressive launch and the car is seeking traction. You must have just hit a slick surface causing traction problems at all 4 wheels. The AWD system can channel as much as 40% of your power to the front. As you were already moving you probably had enough torque to give traction problems across the board.

tom97c4s

I have had this happen a few times, but never gave it a second thought. IMHO just because we have AWD does not mean we have unlimited traction.

KC993

[quote]Originally posted by tom97c4s:
<strong>I have had this happen a few times, but never gave it a second thought. IMHO just because we have AWD does not mean we have unlimited traction.</strong><hr></blockquote>

I agreed on this... We had a MY2000 Audi A6 2.7t quattro and it did the same hopping at the place my C4 did as well...

CAA

Thanks for the replies - I think I'll take Silver Bullett's advice and try it under a few other conditions.

CAA

Thanks for the replies - I think I'll take Silver Bullett's advice and try it under a few other conditions. BY the way - was going to put some pics of the car up but am having trouble finding how to attach. Do I need to use UBB code or can I simply attach .jpg files. Anyways, thanks again!

B-Line

Hey CAA,

Click on Upload Photo's at the top of the website and follow the instructions. Once the photo's are loaded onto Rennlist, Click on Image next to the smilie faces and input the address of the photo.

Btw, I have been driving AWD for years, Between my 4x4 suv, my A4, and the S4, I have to completely agree with the above statements. AWD does not equal unlimited traction. I have experienced the same phenomena in every AWD (4WD) car I have ever owned when I pushed the grip beyond it's potential. The cars will always bounce or hop.

My recommendation is next time you are in the rain, try to use this formula for acceleration and steering. car has 100% traction. That traction can be divided. 10% turn, 90% acceleration. OR, 90% turn, 10% acceleration. Or any fraction there of. 50/50, 80/20, etc.
If you exceed that 100% grip, your car will hop.

Think of a string attached to your foot and the steering wheel. as you turn the steering wheel, your foot comes up because the string is pulling on your foot. Once the wheel straightens, you can apply more gas because the string is not loose.

But, if you are slamming your foot to the floor, and turning, something has to give!! you have exceeded 100% traction, therefor resulting in the hop!!

good luck

H20NOO

Worn shocks could exaggerate the problem.

Matt

CAA

B-Line,

Thanks for the advice - you make a very good point. Also, how would I be able to tell if my shocks are worn? Also went and uploaded pics. These aren't very good but I will get my digital camera from my fiancee this weekend and try to take more.


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