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We've just gotten done with our testing and specification of a BWR Spec OS Giken diff. Unique pre-load, accel/decel rates. We've taken the transmission out and apart so many times over the last 6 months to dial in the performance. The result is that the BWR spec will give more acceleration out of the corner while maintaining fantasic corner entry characteristics. The only diff to give 100% lockup. Ideal for the autocrosser, road/drag racer, or boosted Lotus owner.

Regular Clutch diffs cannot get to 100% lockup or they lockup abruptly because they don't have enough plates in the diff.

The Blackwatch Spec OSG locks 100% AND does it without obnoxious corner entry or exit push! Steer with the throttle or the brake.

The OS Giken was the single biggest improvement we made to the XP car last year and I don't think we would have won Nationals without it.

Just got 2 air-shipped from Japan. We sold the first one before it hit US Airspace! More to follow.....

:shift:
 

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Discussion Starter #3
We have the 1 from the air shipment....
 

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so, this is not meant for track?

How would this compare with the one that Outerplus Ti Racing using on their Exige 1.8way?
 

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so, this is not meant for track?

How would this compare with the one that Outerplus Ti Racing using on their Exige 1.8way?
I don't know anything about Outerplus. Ours will have more corner exit thrust and be far more neutral on corner entry than the standard OSG. If theirs is 1.8 way it likely locks up even more on decel. Many of the Japan diffs are used for drifting....
 

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Definitely liking the look of this. Is there a place I can read up on the stock diff? Is the stock one torsen?

Would really like to be able to read up for comparison's sake.

How much for the BWR OS Giken?

The os giken lsd was the best mod on my 370z.
 

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so, this is not meant for track?

How would this compare with the one that Outerplus Ti Racing using on their Exige 1.8way?
I have the ATS carbon 1.8 way LSD installed 2 months. There are no big differences between 1.5 and 1.8 way. I have never been tracked mycar yet. But my first impression on street driving is that it eliminated the understeering problem i used to have with open differential. It is much more easy to throttle steer with the1.8 way LSD.
 

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Discussion Starter #9
The stock LSD is a torsen. The problem with Torsens are that they cannot achieve true 100% lockup so you will always be leaving some grip on the table. Additionally, if you get a wheel up i.e. curbing or bump etc, the Torsen looses all torque, i.e. grip goes to zero.


The BWR OS Giken is currently on-sale for the same price as a regular OS(Normally $150 more). We use a different center ring with less decel lock to allow the car to turn-in much better both in traditional corner entry or slaloms. Additionally, we have different lockup ramp-rates to achieve max grip on acceleration.
 

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The stock LSD is a torsen. The problem with Torsens are that they cannot achieve true 100% lockup so you will always be leaving some grip on the table. Additionally, if you get a wheel up i.e. curbing or bump etc, the Torsen looses all torque, i.e. grip goes to zero.
hence why Wavetrack torsen's and the like exist.

Personally, I can't think of anything worse than having a diff that can 100% lock (outside of drag racing).

As I am sure I must have said several hundred times before, if your spinning wheels, sort the suspension out, and LSD is a sticking plaster to the real problem, ie lack of grip (which an LSD will not improve).
 

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hence why Wavetrack torsen's and the like exist.

Personally, I can't think of anything worse than having a diff that can 100% lock (outside of drag racing).

As I am sure I must have said several hundred times before, if your spinning wheels, sort the suspension out, and LSD is a sticking plaster to the real problem, ie lack of grip (which an LSD will not improve).
Dunno about that, I have put spools or just welded the spiders in plenty of vehicles.
 

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Discussion Starter #14
If you have enough torque through gear multiplication and engine torque the 100% lock capability is pretty important. Probably less so on a road-race car than autox. The key thing with the Giken is that it has so many plates that the lockup is gradual and progressive so you don't get a sharp bite on corner exit.

I've driven an open diff car in an autox and the inside wheelspin is slow.

Lastly, I assume that since F1 cars uses diffs its OK for the rest of us! :p
 

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If you have enough torque through gear multiplication and engine torque the 100% lock capability is pretty important. Probably less so on a road-race car than autox. The key thing with the Giken is that it has so many plates that the lockup is gradual and progressive so you don't get a sharp bite on corner exit.

I've driven an open diff car in an autox and the inside wheelspin is slow.

Lastly, I assume that since F1 cars uses diffs its OK for the rest of us! :p
like I have already said, if you spinning the inside wheel sort out the suspension.

yes, ultimately, as LSD cam be helpful, but one that cam 100% lock on a car like the Elise is asking for tail-happy handling, fun but not fast.

So, what your saying is this is just a conventional platted diff?

care to share what ramp angles and pre-load it has?
 

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Discussion Starter #16
Simon, I won't engage with you further. You really don't know what you're talking about w.r.t. this differential and your "truisms" are not. Have a nice day.
 

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Simon, I won't engage with you further. You really don't know what you're talking about w.r.t. this differential and your "truisms" are not. Have a nice day.
in other words, you have no idea what the answer is then?

Look, LSD's are hardly rocket science, they have been around for more years than you have!

unless your tying to tell us all that this is some new fangled technology, that just happens to use plates but has some 'magic pixis' that engage them? (as opposed to the usual forward/reverse ramps and spring pre-load).

Or is this more a case of toys and pram?
 

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:mw::popcorn:
well, as you clearly CBA to answer any basic info on this, I went looking...

Here is a good description of it, looks like an variation on the traditional cone based plated diff (looks similar to the design that Hewland use with their Powerflow diffs).

so, back to the question, what ramp angles etc. have you specified?
 

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Discussion Starter #20
The ramp angles are proprietary and in your case, whatever, we've tested, chosen, and won with will obviously be wrong as far as you're concerned.
 
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