AU..to lsd vs open wheeler ..the truth???

**Stav** · 16-10-2005, 07:18 AM

I have been dodging the lsd install as I just dont believe they are as safe as an open wheeler.They are great for traction and down the 1/4 but have heard time and time again that they arent as safe.

I would like an lsd for the sake of launching the car at more rpm and avoiding wheelspin. So the question on my mind is...do I just slap some gears in the bum..or do lsd with gears?? .

Dodge · 16-10-2005, 07:34 AM

locker diffs are only unsafe in the wet with a ******** behind the wheel

rag top · 16-10-2005, 07:35 AM

Go the LSD.

XR's have them, and they are considered safe. I'd definately get one if I was upgrading my diff.

Lockers on the other hand are not safe but better than LSD's for traction.

16-10-2005, 07:42 AM

i don't reckon standard lsd diffs such as one's in xr's are anymore leathel in the wet than an open wheeler ,its only mini spools that are scarey

16-10-2005, 08:09 AM

I would only only purchase a RWD car with one ,I would hate to go back to a car with a single spinner . I belive they are safer by far wet or dry ,get the LSD and you will never look back

AU-MUSTD · 16-10-2005, 08:44 AM

I didnt feel any difference in launch grip between the two lsd's l owned and my currant standard diff. I was dissapointed that my lsd's would still single spin at the drop of a hat.

Kenaz · 16-10-2005, 10:10 AM

LSDs are only unsafe if you misbehave. If you drive normally you won't have a problem.

**Stav** · 16-10-2005, 10:28 AM

With the high stall and some advice from forum members I have been stalling and testing takeoff.I can stall up to 2400 rpm before taking off like a slingshot.At 2600 and up it wheelspins too much.Would the lsd help me in this department?

dansedgli · 16-10-2005, 10:41 AM

Yes it would, that wheelspin would become a chirp while you launch hard into the distance.

2 wheels are always better than 1.

neb · 16-10-2005, 10:45 AM

yes get lsd definately... you'll wonder how you ever lived with a single spinner. much better traction.. and safer too in my opinion more predictable

**Stav** · 16-10-2005, 10:54 AM

Thanks Ben and Dan thanks heaps....I am thinking of 3.7 as I have driven a ba with 3.45 and I know I will not be happy at all if I settled. I will be getting the 3.7 lsd then.I will be running standard tyres with the set up too. 205/15/65?
My speedo correction will be to take out the speedo assembly and repaint the numbers.I never do 180 kmph ..I may even black those numbers out.My new top speed will be 156 kmph.The only thing is what rpm I will be doing?Perhaps a cog from a 3.45 tranny will simply leave a total difference of 7% error and a higher speed limti which I can live with both..

xr8ute · 16-10-2005, 11:02 AM

Quote:

Originally Posted by useless

My speedo correction will be to take out the speedo assembly and repaint the numbers

Would that be legal? Wouldn't want to nullify your insurance...

**Stav** · 16-10-2005, 11:05 AM

Quote:

Originally Posted by xr8ute

Would that be legal? Wouldn't want to nullify your insurance...

Then mate I will just leave it alone and put 3.45 cog in the box which will give a closer 7 % error not 14%.the car will rev through gears harder

**Stav** · 16-10-2005, 11:09 AM

What were those famous words????"Its Alive Its Alive ,Aliveeeeeeeeee"

muahahaha!
Thanks for the support all.
If I crack a 15.5 we all know that all the bolts I pulled out went back in!!

:

MrQuan · 16-10-2005, 04:19 PM

Quote:

Originally Posted by useless

My speedo correction will be to take out the speedo assembly and repaint the numbers.

That won't help. I recently went from a 3.23 open wheeler to a 3.7 LSD. You need a speedo corrector (you can get a kit from Jaycar) otherwise your transmission shifts are all out of whack.

Quote:

Originally Posted by xr8ute

Theres a Jaycar kit to do the same as well.

As I understand it, the signal goes from the VSS to the EEC via the dash. So you would need two speedo correction units to correct the speedo and keep the standard auto shiftpoints...

i.e. one between the VSS and the dash to correct speedo, and one between the dash and the EEC to convert back to stock signal.

You only want one unit (between the VSS and dash) the ECU needs the corrected reading as much as the speedo (by putting a second corrector in you're re-introducing the error again for the ECU!), otherwise your shift points will still be out.

**Stav** · 16-10-2005, 04:22 PM

Mr Quan waht happens if you accelerate hard now?Do you hit any speed or rev limiters.

**Stav** · 16-10-2005, 04:38 PM

Quote:

Originally Posted by useless

Mr Quan waht happens if you accelerate hard now?Do you hit any speed or rev limiters.

Almost got a straight answer...sounds like the car wont go properly without speedo correction..???

MrQuan · 16-10-2005, 05:44 PM

Quote:

Originally Posted by useless

Mr Quan waht happens if you accelerate hard now?Do you hit any speed or rev limiters.

I have a speedo corrector kit, so it's ok usually. If I have it on power mode and floor it I sometimes hit the rev limiter for a second before it changes from first to second - but that's most likely due to my transmission being shagged (in need of a rebuild).

My speed limiter did come down by about 30 to 40kmph, but has been corrected since I installed the speedo corrector kit from Jaycar.

xr8ute · 16-10-2005, 11:01 AM

From the factory, the cone-type LSD's in the AU are not great for traction...too loose, but safe-ish when wet.

If the factory LSD was shimed up tighter, you will get much better traction in the dry and let you launch much harder against your converter. As Dan said, 2 is better than 1.

I reckon LSD in the wet can be more dangerous than an open diff, especially if you are not 100% alert. At least they are predictable...if the wheels start spinning, you will need to grab some opposite lock and ease off the go pedal ;)

**Stav** · 16-10-2005, 11:03 AM

My diff rebuilder uses holden lsd centres because they are better/tighter

dansedgli · 16-10-2005, 11:11 AM

When I changed the gears in my EB the speedo was a bit out. I went from 3.27 to 3.45 LSD. I bought an Apexi Rev Speed Meter. Its a bit ricey but allows you to get a speed input from your ECU and the RSM will allow you to change the reading and show the correct speed on the unit.

I sold it to santoitaliano and I think he made it work so it changed what the factory speedo said as well. They can be had for about $300 and once you have made it work with your speedo you can hide it somewhere. You wont need to buy a new cog.

It works like a Gtech as well to measure performance.

**Stav** · 16-10-2005, 11:33 AM

gee man thanks for that....Im stoked..

xr8ute · 16-10-2005, 12:39 PM

Theres a Jaycar kit to do the same as well.

As I understand it, the signal goes from the VSS to the EEC via the dash. So you would need two speedo correction units to correct the speedo and keep the standard auto shiftpoints...

i.e. one between the VSS and the dash to correct speedo, and one between the dash and the EEC to convert back to stock signal.

jonbays · 16-10-2005, 03:32 PM

An LSD is going to make a huge difference to a front engine rear drive sedan in testing conditions like a hill climb or race track event or dragstrip but for the money for a 100% street driven car they are worthless for anything except really EXCITING burnouts. With an LSD you can do big snaky burnouts all over the road like the real hoons can. In the wet EXCITING can become F***ING DANGEROUS.

In my long wheelbase wagon traction control is just fine for wet weather and in the dry it rarely interferes so an LSD will do very little for me or you.

EFFalcon · 16-10-2005, 03:38 PM

any one suggesting LSD is more dangerous then a SS is crazy.
a SS can STILL spin both wheels if pushed hard enough, and if your driving hard enough to be unsafe with an LSD... then you're an idiot.
drive the conditions, atleast with an LSD you *KNOW* the car is going to spin both wheels, good luck trying to predict that with an SS.

an LSD will help plenty with traction on the street, and i'd say they're deffinately money well spent.

**Stav** · 16-10-2005, 03:58 PM

I have always found the single spinners very predictable to drive.Driving some lsd equipped cars I have noticed more side skipping at the rear .I drove 2 lsd equppied cars and had the same behaviour twice.My broinlaw owns a potential 10 second cobra and has also mentioned that the lsd may flip the back out alot easier than single spinner..

Now though with an auto with the ability to launch up to 3300 rpm I would like to think that I can use as much of its potential in the appropriate times such as a 1/4 mile stint.Whether I go lsd or stay open wheeler the 3.7 's will be the next move.

EFFalcon · 16-10-2005, 05:15 PM

Quote:

Originally Posted by useless

I have always found the single spinners very predictable to drive.Driving some lsd equipped cars I have noticed more side skipping at the rear .I drove 2 lsd equppied cars and had the same behaviour twice.My broinlaw owns a potential 10 second cobra and has also mentioned that the lsd may flip the back out alot easier than single spinner..

the LSD is MEANT to skip sideways if it breaks traction.
the point is... it will do it EVERY time...
a SS *Can* do this, not every time, but it can... hence my comment on the LSD being predictable.
yes an LSD once it looses it is harder to get back in, but its also allows you to push harder.
give me an LSD over a SS any day, atleast i know what the rear end is going to do.

**Stav** · 16-10-2005, 05:20 PM

LSD is going to happen.Doesnt cost all that much..should be able to use alot more of those 3300 odd rpm off the line.

However the ratio change is ticking me off. Sounds like a can of worms that I don't need. I know that there is much info out there but it would be great to find someone who has done it without a j3 chip in a auto and how it went..

xr8ute · 16-10-2005, 05:30 PM

Quote:

Originally Posted by useless

However the ratio change is ticking me off. Sounds like a can of worms that I don't need. I know that there is much info out there but it would be great to find someone who has done it without a j3 chip in a auto and how it went..

You and me both. When I get my diff rebuilt, assuming it's only a few hundred more, I'd like to get a set of 3.9's in there.

I don't wont to waste $600 on a ChipTorque when Edit is so close. But I don't want to waste my track day at WSID on the 30th with auto-shift, rpm-limit, and speed-limit problems because of a confused EEC...

Need to do some more research me thinks, and if I can't find an answer I'll stick with the 3.45's

jonbays · 16-10-2005, 04:24 PM

Quote:

Originally Posted by EFFalcon

any one suggesting LSD is more dangerous then a SS is crazy.
a SS can STILL spin both wheels if pushed hard enough, and if your driving hard enough to be unsafe with an LSD... then you're an idiot.
drive the conditions, atleast with an LSD you *KNOW* the car is going to spin both wheels, good luck trying to predict that with an SS.

an LSD will help plenty with traction on the street, and i'd say they're deffinately money well spent.

SS is easier to drive and quite predictable when pushed past sensible limits on purpose or by accident. I have seen a million SS hoons smoke up their tyres and not get into grief but I have seen quite a few LSD hoons lose it big time and crash into parked cars fences etc. LSD is not so easy or predictable but has much higher limits before it does really lose it.

The q is good value for a street car not a race car where theres no argument really.