diff question

Reply Subscribe

Thread Tools

Search this Thread

11-19-2012, 02:39 AM

#31

powdrhound

Rennlist Member

Join Date: Dec 2010

Posts: 7,112

Likes: 4

Received 1,920 Likes on 1,118 Posts

Quote:

Originally Posted by Macster

How can you think about venturing onto a track with a car that is not 100% mechanically sound?

I could envision catastrophic failure with the diff blowing up/coming apart and the car leaving the track or even worse the failed diff littering the track with diff shrapnel and diff fluid and someone else leaving the track with maybe dire consequences.

Get the diff fixed. Drive the car some to shake down the diff repair. Then if all is well hit the track. The odds are higher that is all you will hit.

The diff is not going to explode unless it's completely shot I would think. It's just that the Porsche diffs are crappy in that they are set up with a tiny preload (around 11 ft/lbs. IIRC) which pretty much makes it an open diff under braking once you put a little wear on it, a couple of track days actually. It will still lock under acceleration but will be pretty useless under braking. Most guys just have the factory diffs rebuilt with Guard plates and set up with a much higher preload. My Guard diff has around a 60 ft/lb preload.

Reply Like

11-19-2012, 11:47 PM

#32

tguaturbo

Banned

Thread Starter

Join Date: Aug 2011

Location: Ohio

Posts: 799

Likes: 0

Received 0 Likes on 0 Posts

Out on Day 2 with the car and odly enough, no tail wiggle under 100+ mph braking, not once. I don't have any shims in the wing either. Can't really tell if this lsd mod is something I need right now. An instructor who frequents my local track said I should learn to drive the tool as it is first and eventually do the lsd, but not do it while I am learning a different platform.

Not sure what to do now?