Q's after near spin during 1st to 2nd shift (hard on throttle)

mike mueller · 11-28-2003, 08:12 AM

So I'm driving home in the C2 last night from visiting the parents and come up to a light in the middle of nowhere (desserted intersection in Brentwood)

I feel the need to accelerate knowing it's a faily safe place to do so at this time of night and this area....

Light turns green.....hard on the gas in 1st I shift into second at ~7000 rpm and get the car into 2nd gear, all of sudden the rear end steps out a few feet

I correct the steering and stay on the gas and successfully prevented an embarrassing or costly mishap......

What did I do wrong?

Did I release the clutch too fast?

Would have an LSD diff helped?

Tires are 255/40/17's and should have been warm due to the long drive.

jester911 · jester911's Garage

Assuming your rear tires have good tread, you may have just spun in a little oil. LSD would help in that case if oil only on one tire.

Did you feel any wheel spin?

MY83SC · 08:41 AM

Wow....Congrats on the GREAT recovery. Must have been a frightful moment!
Are your tires a bit worn? Sounds, to me, like you passed the adhesion limits of your tires when you throttled into 2nd gear. Perhaps gravel, sand etc. was on the road.
I don't think you did anything technicaly incorrect...You proved a high amount of driving skill by your recovery. And LSD, in MYHOP, would help this sort of thing from happening, a bit less likely.
Glad that you and your car are OK.

Vipergrün · 11-28-2003, 08:37 AM

Sounds like fun! Probably hit a slick spot on the street. I think LSD would help. I have it on my SC and it seems easier to *power* out of situations. Sounds like you did it right

-B

Superman · 11-28-2003, 09:28 AM

The only unusual thing about this story is your sense of surprise. Of course, we have wet roads here most of the time, so that's my bias. But the fact remains that these cars require two hands, two feet, two eyes, two ears and a focused brain.

dd74 · 11-28-2003, 09:45 AM

I think you should look at this as a good learning experience. You've found the adhesion limit of your tires (were the tires cold, by the way), and that if it's the Brentwood I'm thinking of, that the roads can be slick from overspray from sprinklers, plus choppy as some of them are still concrete and old asphalt which has been damaged from subsequent earthquakes and general use.

What street did this happen on?

fintstone · fintstone's Garage

I think shifting too late caused problem.....not producing much at 7k, dropped back into meat of second gear..gobs of torque...broke wheels loose. Good recovery.

masraum · 11-28-2003, 03:42 PM

Sounds like you shifted really hard and found one of those especially slick spots that occur from time to time. Had you only been spinning one tire the rear end wouldn't have stepped out because the non-spinning tire wouldn't have allowed it.

Even with an open differential you can spin both tires equally under the right circumstances (usually far too little traction and gobs of torque).

Depending upon how you got into the throttle and how you let the clutch out you may have been able to shift without the experience, but it is not necessarily an indication that you did anything wrong or anything was wrong/inadequate with the car. If you were spinning both tires (as you almost certainly were to get sideways, squirrelly for you hot rodders

) then an LSD probably wouldn't have done much, maybe allowed you to recover a tad faster, but not necessarily.

I have hit spots before in cars that through nothing other than just flooring the gas when already moving I could spin the tires on cars that were otherwise nearly impossible to spin the tires unless you were really abusing the car, that is because some spots are just always slick.

I'm not sure what condition your tires are in and how cool it was when you did it, but this time of year if the temps are cool and if your tires are already old can also lead to lots of extra wheelspin compared to what you are used to. Performance tires don't like cold weather.

If it surprised you that much it was probably a good thing to experience. You may want to practice it from time to time in the rain in large open spaces, it's a learning experience.

fintstone · fintstone's Garage

I agree with Steve...good thing to experience. A well sorted out Porsche feels like it is glued to the pavement. Makes one a bit overconfident. First time my rear end broke loose scared the hell out of me...it whipped around sooo mucch faster than I was used to in front engine performance cars.