ztriumph

Hello Folks,

Question on the stock rear end. last weekend I installed the Ark Performance Grip exhaust (pics and writeup to be posted this weekend, most challenging part was getting the stock exhaust off the hangers!; uprev tune happening saturday) and when I was backing the car out of my garage I ended up in the grass on a slight uphill embankment outside of my house (side garage has the lift however NOT a straight shot out of the door onto the pavement). Here's where the interesting thing happened:

I ended up getting stuck on the hill. I couldn't get any traction to get up the hill and just sat there spinning. I turned off the VDC to allow a little bit of slip, however just spun. When I got out of the car I checked the rears and only one tire had dug up the earth. There-in lies my question - I thought these cars had some type of posi? There was zero evidence of the other tire spinning. I have a 2007 touring model. I have two modified Triumph TR8's with one of them having a Quaife and the other I put in a mustang 8.8 with 3.55's, and in both cases when I get in the same spot i am able to get up the hill and have tire marks from each side. Is there something wrong with my Z? It has 9k miles on it so I don't think the coupling could be cooked, however does this make sense? It is acting like an open diff.

btw I am just your average backyard mechanic and new to this car, so apologies for this question if it has been covered, but I couldn't find anything.

And for those interested, I ended up using the front tow hook and putting my jeep to good use. terribly embarrassing in front of the girlfriend.....

terrasmak

iTrader: (8)

The VLSD is garbage, and just about no better than an open dif.

Stock2Autocrozz

iTrader: (6)

^^ For DD, the vlsd is fine and even for tracking, depending on the application....there are some members here running ridiculous hp with stock vlsd....so I disagree w/comment but to each their own, benefits can be had elsewhere in the car depending once again on the applications.

*Side note, I do not drive my car in MN winters, thus no snow...and since my car was base I added vlsd to, I have no VDC..imo just another piece I'd have to turn off...let her drift..lol

AngelsVQ

iTrader: (4)

+1 to this

AngelsVQ

iTrader: (4)

-1 to this

terrasmak

iTrader: (8)

All that means is it is impossible for them to put the power to the ground.

Stock2Autocrozz

iTrader: (6)

Never had any problems, those I specifically spoke w before install were adamant and confident. I have no regrets with the choice, and the $ saved went into better engine components, nuff said

terrasmak

iTrader: (8)

The money i spend went to better lap times, and less tire wear. When your not spinning the inside tire cause the car hooks, does give you better tire wear.

davidv

iTrader: (2)

I generally do not drive in the grass. Not sure what tires to recommend.

kakashishin

I'm not going to say the VLSD is the best diff ever, but I'm going to go on a limb and pretend you actually read the why the guy's tires was spinning. If you read it again, he said he was going up hill and the tires spun and pulled up dirt. Obviously he was probably off road, meaning not on tarmac. If you know about any Z that can go off road, let me know. I want that system on my ride. Saying a open diff is better than having no diff is also wrong as two boys, in front of a all girls catholic school full of supermodels, making out. Read up on how diffs work and then say that crap again. Or better yet, go do a road course or some kid of gymkhana and do it with an Open Diff and a VLSD and think about it. Again the VLSD isn't the best limited slip differential, but it's better than nothing.

kakashishin

Besides if you have a modified triumph that only weighs about 1,500lbs less than a Z that might kinda explain why it went up hill and the Z was having problems.

ztriumph

Kakashin & Davidy,

In my post i explained that I was on the grass due to backing out of my side garage (tight turn to stay on the pavement and I didnt make it). Let me be clear, I am not looking for an off-road Z. My question is "is there something wrong with my VLSD, as only one tire dug up my grass vs my expectations of having two sets of tires marks". I am questioning if any one else has been in a situation where they noticed only one tire spinning vs two and if this is normal.

The TR8 is MUCH more difficult to get any traction on the grass. It has 302 lbs RWTQ, absolutely no weight in the rear end and BFG Drg Radials. Yet with the ford 8.8 rear I was able to scramble up.

drivessidewayz

iTrader: (4)

^^lol? I dun think you know who terrasmak is.

As for the OP, I'll join in with the "VLSD sucks" crowd and say that it simply sucks and that's why it happened. Out of curiosity, did both tires have about the same amount of weight on them, or did one have significantly more?

ztriumph

Both tires had approx the same weight. I was concerned that my VSLD could be cooked as I have heard this has been known to happen with these diff's over a period of time and abuse.... My car only has 9k miles on it, and was 'owned by an elderly gentelman who only drove it on Sundays' but then aren't all used cars?

terrasmak

iTrader: (8)

350Z playing in the dirt , we havn't been able to get much info about their setup yet.
http://www.youtube.com/watch?v=jUxgiPiPCDM

Saying the VLSD is no better than an open diff, pretty freaking close. Open dif 100% sucks, VLSD 95% sucks, not much difference. Have i driven on them, yes, my 03 had a VLSD before i installed a real LSD, my 05 had an open diff, now it had a VLSD.

ztriumph

Well, if my Z had something working half this well I think I could've gotten myself unstuck. Hell at the very least I could have had matching tire strips in my side lawn

Jennifer 2

Ztriumph, I also have the VLSD and join the chorus of complaints about the limited usefulness of this thing. My dad taught me to drive back roads and trails in his ancient 1952 Chevy pick up. This was a pretty low-tech truck that would easily get stuck in sand or mud, spinning one wheel uselessly and going nowhere. One trick he taught me was to gently apply the E-brake to fool the differential into thinking the spinning wheel was on firm ground. It’s easy for the engine to overpower the brake, and now with both wheels turning, the car can get going on the loose dirt/grass/snow/ice. I’ve used this technique successfully a few times with my Z.

Hopefully, someone more familiar with the mechanics of this than I am, can give a better explanation of how this works.