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      11-06-2014, 02:31 PM   #1
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Salisbury Limited Slip Conversion

Thoughts?

http://dinancars.com/product/d773-00...ip-conversion/

(my concern is not with a gear ratio change)
Is it significant? Are heavy track cars running similar modifications?

Any one know of any other aftermarket companies offering similar upgrade?
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      11-06-2014, 03:17 PM   #2
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Quote:
Originally Posted by knolow View Post
Thoughts?

http://dinancars.com/product/d773-00...ip-conversion/

(my concern is not with a gear ratio change)
Is it significant? Are heavy track cars running similar modifications?

Any one know of any other aftermarket companies offering similar upgrade?
If you're going to swap out the M-diff for the traditional LSD like this Dinan one, I would suggest contacting diffsonline or blanton and have one custom built for your specific desires (i.e. number of clutch plates, ramp angles for power on/power off, static lockup, etc). You'll save a ton of money going with these guys and also get exactly what you need/want.
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      11-06-2014, 03:20 PM   #3
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+1 on diffsonline and look at OS Giken. They make serious LSDs
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      11-07-2014, 09:17 PM   #4
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Quote:
Originally Posted by CSBM5 View Post
If you're going to swap out the M-diff for the traditional LSD like this Dinan one, I would suggest contacting diffsonline or blanton and have one custom built for your specific desires (i.e. number of clutch plates, ramp angles for power on/power off, static lockup, etc). You'll save a ton of money going with these guys and also get exactly what you need/want.
Thanks a lot. I've been doing a lot of reading and understand the characteristics of "torque" diffs like you mention ramp, clutch plates etc but I can't find the connection to what that translates to performance wise. Literally I mean the recipe of what each characteristics buys and equates to like street versus street/track, versus track/street and just track.
(For the critics street/track is not the same as track/street which is more aggressive than the first)


Quote:
Originally Posted by m3ray View Post
+1 on diffsonline and look at OS Giken. They make serious LSDs
Thoughts on my story above?
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      11-07-2014, 10:00 PM   #5
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Quote:
Originally Posted by knolow View Post
Thanks a lot. I've been doing a lot of reading and understand the characteristics of "torque" diffs like you mention ramp, clutch plates etc but I can't find the connection to what that translates to performance wise. Literally I mean the recipe of what each characteristics buys and equates to like street versus street/track, versus track/street and just track.
(For the critics street/track is not the same as track/street which is more aggressive than the first)


Thoughts on my story above?
You can select whatever gearing you want. The higher the gearing the more acceleration, but you lose top end speed. As for the clucth LSD you get real lock up of the wheels that holds through cornering.

You have to determine the right mix of gearing, agressiveness of lock-up when it comes to street/track. But that is really the driver decision as many people have different tolerance for NVH. Clucth LSDs are known to chatter and pop and they vary in how progressive they lock-up. All part of the action of the clutches.

I like the OS cause you can set the LSD to 1 way, 1.5 or 2.0, (2.0 would be straight track). You can also customize the angles and ramp up rates between the clutches changes how progressive the lock up rate, but that needs to be done by a speciality shop (Dan -diffsonline, are great shop here in North East)

Have a look at this link too, its a good read.

http://www.osgiken.net/products.php?product=lsd

Last edited by m3ray; 11-07-2014 at 10:25 PM..
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      11-08-2014, 09:24 AM   #6
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yes, a clutch type lsd is a must have for a track car!

i tried all units available on the market in my e92. here are my thoughts:
http://www.m3post.com/forums/showthread.php?t=788992

the osg was the worst performing of all units i tried. the dinan setup is too weak for track use and the price tag is crazy. best unit would be a oe gt4 unit or a heavily modified zf unit (dinan uses a non-modified one).
i have all units in stock... but i am located in germany :-(
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      11-08-2014, 09:34 AM   #7
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here are some pics of the disassembled units on the market
http://www.m3racing.de/sperre.html
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      11-08-2014, 08:34 PM   #8
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Quote:
Originally Posted by driftflo View Post
yes, a clutch type lsd is a must have for a track car!

i tried all units available on the market in my e92. here are my thoughts:
http://www.m3post.com/forums/showthread.php?t=788992

the osg was the worst performing of all units i tried. the dinan setup is too weak for track use and the price tag is crazy. best unit would be a oe gt4 unit or a heavily modified zf unit (dinan uses a non-modified one).
i have all units in stock... but i am located in germany :-(
Driftflo

Thanks. You did what I wish I could do. And like you said my concern is obviously the osg and other website brand order form type lsd's are really tricky to setup with the amount of parameters you can change and the few setup-informations that are shared.
Seems like the OE GT4 is the best all around setup. My next concern would be getting more feedback from trackers that use it.
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      11-10-2014, 11:23 AM   #9
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Quote:
Originally Posted by knolow View Post
Seems like the OE GT4 is the best all around setup. My next concern would be getting more feedback from trackers that use it.
This is the same conclusion I came to as well, Drexler diff. The only problem is, I cannot find a place in the USA that sells them. Maybe I am not looking hard enough?
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      11-12-2014, 09:34 AM   #10
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Quote:
Originally Posted by driftflo View Post
here are some pics of the disassembled units on the market
http://www.m3racing.de/sperre.html
Quote:
Originally Posted by italyix View Post
This is the same conclusion I came to as well, Drexler diff. The only problem is, I cannot find a place in the USA that sells them. Maybe I am not looking hard enough?
Hmmm, I havent even gotten there yet (finding a a suppler).

Driflo Any thoughts on vendors for the GTS Dif in the states?
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      11-12-2014, 09:43 AM   #11
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Salisbury units are really nice and much better than stock. The Dinan unit looks pretty good and OS Giken is a masterpiece and extremely flexible. Turner uses them in their racecars.

However, i've never liked to install OS Gikens with their "off the shelf" settings. Check out my article to see how OSG's work and how to set them up:


http://www.motoiq.com/MagazineArticl...ferential.aspx

Billy
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      11-12-2014, 02:17 PM   #12
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Quote:
Originally Posted by knolow View Post
Driflo Any thoughts on vendors for the GTS Dif in the states?
the GTS diff is the same crap as the one in the standard m3! you would need a GT4 (racecar) unit, only there the drexler is installed!

i do not know any sources in the states.
i currently have a drexler gt4 unit in a i=3.85 pumpkin installed laying around here. and i have a drexler with a 4.10 gearset and a naked drexler unit not assembled at all yet.
and i have a lot of my custom units which are quite similar to the drexler concerning setup and materials used (same clutches) but way cheaper.

i.e. the 45% 2-way setup with double the amount of clutches than the one on the dinan picture would cost eur 1.300,- plus shipping. the 65% version with three times the amount of clutches costs eur 1.600,-
the drexler oe unit costs eur 2.000,-

i do not know if importing them would make any sense. shipping a lsd unit should be possible at a reasonable price. but shipping a whole pumpkin would be very expensive. so you still need to have someone in the US who installs it for you.
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      11-12-2014, 02:39 PM   #13
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Quote:
Originally Posted by Billj747 View Post
The Dinan unit looks pretty good...
looking good doesn't necessarily mean locking good!


Quote:
Originally Posted by Billj747 View Post
and OS Giken is a masterpiece and extremely flexible. Turner uses them in their racecars.
why would you call it a masterpiece? i agree that it really looks nicely! but as soon as it is installed this "feature" is gone. but what technical aspect would you emphasize to call it "masterpiece"?
did turner also try the gt4 unit or do they use it because they sell it?

i bought, dis- and assembled, installed and tested all lsd units available worldwide for the e92 m3 myself (except cusco, this one is still missing) and i even tried different setups of various units. so my ratings are based on experience and comparison. and my rating for the osg against the competition is... well... not so good.


Quote:
Originally Posted by Billj747 View Post
However, i've never liked to install OS Gikens with their "off the shelf" settings.
but this is one of the most important things for a "normal" customer. how many customers of such a unit will disassemble and adjust a new-bought lsd unit prior to installation (except you and me *g*)?
the stock m3 e92 setup of the osg superlock is a joke. it doesn't lock at all. [and i can hardly believe that your setup locks effectively in the nsx when i look at the ramps, active clutchpacks and neg. preload setup you did... but ok, it is another car and another lsd unit.] the next setup i tried after talking to the osg guys was locking way to hard. after the second try i lost my patience and gave the next manufacturer a try as i am not the R&D guy of osg. i spent a lot of money for this "premium" lsd and i expect to also buy a setup that performs at least quite ok!


Quote:
Originally Posted by Billj747 View Post
Check out my article to see how OSG's work and how to set them up:

http://www.motoiq.com/MagazineArticl...ferential.aspx
great website and this article is outstanding! although i do not agree in all points concerning setup the descriptions are really good and the only serious source i found concerning osg lsd units and substanciated infos on their setup and functionality.
the osg website and the explanation of their own units is only proof, that they do not know themselves how clutch type lsd units do work.
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      11-12-2014, 07:05 PM   #14
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Quote:
Originally Posted by driftflo
Quote:
Originally Posted by knolow View Post
Driflo Any thoughts on vendors for the GTS Dif in the states?
the GTS diff is the same crap as the one in the standard m3! you would need a GT4 (racecar) unit, only there the drexler is installed!

i do not know any sources in the states.
i currently have a drexler gt4 unit in a i=3.85 pumpkin installed laying around here. and i have a drexler with a 4.10 gearset and a naked drexler unit not assembled at all yet.
and i have a lot of my custom units which are quite similar to the drexler concerning setup and materials used (same clutches) but way cheaper.

i.e. the 45% 2-way setup with double the amount of clutches than the one on the dinan picture would cost eur 1.300,- plus shipping. the 65% version with three times the amount of clutches costs eur 1.600,-
the drexler oe unit costs eur 2.000,-

i do not know if importing them would make any sense. shipping a lsd unit should be possible at a reasonable price. but shipping a whole pumpkin would be very expensive. so you still need to have someone in the US who installs it for you.
So, which of ur units would be the equivalent or better to the Drexel unit? Seems the one you sells is the best option and cheaper than as well. If it wasn't for tenge fact that I'm trying to buy a house literally right now, I would have ordered one from u. I might pull the trigger in a few months though, shipping can't be that expensive for just the diff itself.
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      11-12-2014, 09:17 PM   #15
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Quote:
Originally Posted by Billj747 View Post
Salisbury units are really nice and much better than stock. The Dinan unit looks pretty good and OS Giken is a masterpiece and extremely flexible. Turner uses them in their racecars.

However, i've never liked to install OS Gikens with their "off the shelf" settings. Check out my article to see how OSG's work and how to set them up:


http://www.motoiq.com/MagazineArticl...ferential.aspx

Billy
Billy thank you. Very informative and the first time I was able to understand what each feature of the clutch lsd effects i.e. differential configuration, setting 1 for track versus setting 2 for drifting.
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      11-12-2014, 09:21 PM   #16
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Quote:
Originally Posted by driftflo View Post
looking good doesn't necessarily mean locking good!



why would you call it a masterpiece? i agree that it really looks nicely! but as soon as it is installed this "feature" is gone. but what technical aspect would you emphasize to call it "masterpiece"?
did turner also try the gt4 unit or do they use it because they sell it?

i bought, dis- and assembled, installed and tested all lsd units available worldwide for the e92 m3 myself (except cusco, this one is still missing) and i even tried different setups of various units. so my ratings are based on experience and comparison. and my rating for the osg against the competition is... well... not so good.



but this is one of the most important things for a "normal" customer. how many customers of such a unit will disassemble and adjust a new-bought lsd unit prior to installation (except you and me *g*)?
the stock m3 e92 setup of the osg superlock is a joke. it doesn't lock at all. [and i can hardly believe that your setup locks effectively in the nsx when i look at the ramps, active clutchpacks and neg. preload setup you did... but ok, it is another car and another lsd unit.] the next setup i tried after talking to the osg guys was locking way to hard. after the second try i lost my patience and gave the next manufacturer a try as i am not the R&D guy of osg. i spent a lot of money for this "premium" lsd and i expect to also buy a setup that performs at least quite ok!



great website and this article is outstanding! although i do not agree in all points concerning setup the descriptions are really good and the only serious source i found concerning osg lsd units and substanciated infos on their setup and functionality.
the osg website and the explanation of their own units is only proof, that they do not know themselves how clutch type lsd units do work.
Quote:
Originally Posted by driftflo View Post
looking good doesn't necessarily mean locking good!



why would you call it a masterpiece? i agree that it really looks nicely! but as soon as it is installed this "feature" is gone. but what technical aspect would you emphasize to call it "masterpiece"?
did turner also try the gt4 unit or do they use it because they sell it?

i bought, dis- and assembled, installed and tested all lsd units available worldwide for the e92 m3 myself (except cusco, this one is still missing) and i even tried different setups of various units. so my ratings are based on experience and comparison. and my rating for the osg against the competition is... well... not so good.



but this is one of the most important things for a "normal" customer. how many customers of such a unit will disassemble and adjust a new-bought lsd unit prior to installation (except you and me *g*)?
the stock m3 e92 setup of the osg superlock is a joke. it doesn't lock at all. [and i can hardly believe that your setup locks effectively in the nsx when i look at the ramps, active clutchpacks and neg. preload setup you did... but ok, it is another car and another lsd unit.] the next setup i tried after talking to the osg guys was locking way to hard. after the second try i lost my patience and gave the next manufacturer a try as i am not the R&D guy of osg. i spent a lot of money for this "premium" lsd and i expect to also buy a setup that performs at least quite ok!



great website and this article is outstanding! although i do not agree in all points concerning setup the descriptions are really good and the only serious source i found concerning osg lsd units and substanciated infos on their setup and functionality.
the osg website and the explanation of their own units is only proof, that they do not know themselves how clutch type lsd units do work.
Driftflo I like your passion, it makes me believe you really know your stuff. But understand I can't just take your word for it when there are so many reviews and others that keep pushing the OS Giken here in the states. It doesn't help that your not here either to have others collaborate. So I have more questions as I want to get the right LSD...

Is your review really only based on drifting? (you say it's not, but you admit your heavy into drifting; wondering if there is a bias) Would that explain why you like the more aggressive lockup setups?

I'm in to the track and improving my lap times not drifting. I just want the ideal LSD for tracking so I don't waste my money. My bottom line is that I need a setup that will help apply even power as soon as I give throttle to help track time and avoid wheel spin/sliding and I don't want chatter (from lsd setup) when I late brake to take a turn. Thoughts on my setup?
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      11-13-2014, 02:02 AM   #17
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Quote:
Originally Posted by italyix View Post
So, which of ur units would be the equivalent or better to the Drexel unit? Seems the one you sells is the best option and cheaper than as well. If it wasn't for tenge fact that I'm trying to buy a house literally right now, I would have ordered one from u. I might pull the trigger in a few months though, shipping can't be that expensive for just the diff itself.
the "best" unit is the one that is set up on your individual needs. if a customer tells me what he wants or where and how he wants to drive the car i can configure the lsd for that certain needs. i did a lot of racecar lsd setups but also loads of street driven units and units that need to do both. if the hardware-basis for that individual setup is a drexler, a titan, my own one or whatever is not really important.
the manufacturer is more important if you will just put the new unit in your pumpkin without reconfiguring it.
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      11-13-2014, 02:10 AM   #18
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Quote:
Originally Posted by knolow View Post
Is your review really only based on drifting? (you say it's not, but you admit your heavy into drifting; wondering if there is a bias) Would that explain why you like the more aggressive lockup setups?
my reviews are not based on drifting at all. i am earning my money with drift-courses here in germany but i am also a driving safety trainer for german automobile club and in that function i can use their training locations where i do the "objective" basic testing like putting one side of the car on slippery surface and one on grippy tarmac. there you can check the locking capability easily and without any personal preferencen on driving style.

of course i also test my diffs in real world conditions on the street and on racetracks, especially nürburgring nordschleife, where i take part in clubracing - not drifting ;-)


Quote:
Originally Posted by knolow View Post
I'm in to the track and improving my lap times not drifting. I just want the ideal LSD for tracking so I don't waste my money. My bottom line is that I need a setup that will help apply even power as soon as I give throttle to help track time and avoid wheel spin/sliding and I don't want chatter (from lsd setup) when I late brake to take a turn. Thoughts on my setup?
yes ;-)
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      11-13-2014, 09:44 AM   #19
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Quote:
Originally Posted by driftflo View Post
why would you call it a masterpiece? i agree that it really looks nicely! but as soon as it is installed this "feature" is gone. but what technical aspect would you emphasize to call it "masterpiece"?
did turner also try the gt4 unit or do they use it because they sell it?
It's a "masterpiece" due to the quality of the unit and the unique design with tremendous flexibility and different aspects that you can adjust. Masterpiece by design and operation, not just visual.

Quote:
Originally Posted by driftflo View Post
i bought, dis- and assembled, installed and tested all lsd units available worldwide for the e92 m3 myself (except cusco, this one is still missing) and i even tried different setups of various units. so my ratings are based on experience and comparison. and my rating for the osg against the competition is... well... not so good.
What was your issue with the OSG?

Quote:
Originally Posted by driftflo View Post
but this is one of the most important things for a "normal" customer. how many customers of such a unit will disassemble and adjust a new-bought lsd unit prior to installation (except you and me *g*)?
the stock m3 e92 setup of the osg superlock is a joke. it doesn't lock at all. [and i can hardly believe that your setup locks effectively in the nsx when i look at the ramps, active clutchpacks and neg. preload setup you did... but ok, it is another car and another lsd unit.] the next setup i tried after talking to the osg guys was locking way to hard. after the second try i lost my patience and gave the next manufacturer a try as i am not the R&D guy of osg. i spent a lot of money for this "premium" lsd and i expect to also buy a setup that performs at least quite ok!
I agree, which is why I always mention this issue and my article with my praise for the OSG. If you invest that much money in an LSD, it would be wise to become educated on the component and set it before you install it. It's not hard to disassemble it or have a shop disassemble and reconfigure it to your specific application and power levels. Criticizing that is like installing coiloves with the 'off the shelf' settings and complaining its not ideal for your car.

I am surprised and question your claims that the OS Giken "Super Lock" LSD did not lock with the factory settings. That is what OSG is known for and prides themselves that their diffs lock 100%. In every off the shelf OSG setup that I have driven, the LSD locks too aggressively and too soon. I have always recommended deactivating plates and delaying and softening the lock as described in my article for a better performing and smoother engagement for both track and especially street use.

With doing the above adjustments to make the OSG less aggressive, I have never had inside wheel spin despite driving cars with over 800whp including NA and Turbo: NSXs, 350Zs, 370Zs, M3s, EVOs, RX7s, RX8s, Miatas, Mazdaspeed 3s, S2000s, Boxters, STIs, etc...

Quote:
Originally Posted by driftflo View Post
great website and this article is outstanding! although i do not agree in all points concerning setup the descriptions are really good and the only serious source i found concerning osg lsd units and substanciated infos on their setup and functionality. the osg website and the explanation of their own units is only proof, that they do not know themselves how clutch type lsd units do work.
I'll take that as a compliment.


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      11-13-2014, 12:14 PM   #20
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Quote:
Originally Posted by Billj747 View Post
What was your issue with the OSG?
here is what i wrote about it in the other thread:

"... build quality, materials used and the surface finishing is really thumbs up.
but once installed i was pretty much disappointed on the locking capabilities: it hardly locked at all... it simply felt like an open unit.
after discussing with the supplier and manufacturer we were pretty sure that the neg. preload setup was to high. i got some new pressure plates and a different setup suggestion. i am really curious an how it will perform in the new spec which i will assemble these days as i am pretty convinced of the general design and the negative preload idea in theory. i guess i will only need to find a proper setup (which should normally be done by the manufacturer but well...)"

...

"a few days ago i put my new os giken setup in my m3 with the 60/60 instead of the 35/25 ramps and 7 instead of 5 active clutchpacks. and i also reduced the negtive preload from 336 to 224Nm.

before:


after:


here are some more pictures of my new setup:
http://www.m3racing.de/umbau.html#8


now it locks way to hard. i tracked the car yesterday and it was really nasty to drive. well, at least it is the proof that the unit works at all (after the weak locking performance of the spec-s). i am really wondering what setups other guys are driving in their track cars???

as os giken is said to be quite popular in the states, can anybody out there tell me what setup they use in an M3 racecar (or other FR cars)?"

...
[and i just saw we discussed on this in the other thread... this is what i wrote to you:]

"the off the shelf one had only 5 out of 7 clutchpacks activated on each side:
furthermore it had 336kg neg. preload.


it didnt lock at all... no noise, no problems in normal driving... but massive single wheelspin when driven hard.

then i changed pressure plates to more shallow ramps, reduced neg. preload to 224kg and activated all clutchpacks what lead to an massive lockup even in normal driving.


next up i'll change the pressure plates back to the spec-s version and leave all clutchpacks engaged and the neg. preload at 224kg."



if i have some leisure time i will give the osg a third (and last) try. so what setup would you suggest me?


Quote:
Originally Posted by Billj747 View Post
I agree, which is why I always mention this issue and my article with my praise for the OSG. If you invest that much money in an LSD, it would be wise to become educated on the component and set it before you install it. It's not hard to disassemble it or have a shop disassemble and reconfigure it to your specific application and power levels. Criticizing that is like installing coiloves with the 'off the shelf' settings and complaining its not ideal for your car.
well, changing damper setup requires a few seconds. changing the lsd setup takes a day (taking out the pumpkin, removing the lsd, removing the ringgear, changing the setup, and all that vice versa). it is simply not realistic that a customer will do this. and as not even most of the resellers know how to set things up right, the customer doesnt know for sure!


Quote:
Originally Posted by Billj747 View Post
I am surprised and question your claims that the OS Giken "Super Lock" LSD did not lock with the factory settings. That is what OSG is known for and prides themselves that their diffs lock 100%. In every off the shelf OSG setup that I have driven, the LSD locks too aggressively and too soon. I have always recommended deactivating plates and delaying and softening the lock as described in my article for a better performing and smoother engagement for both track and especially street use.
the 100% lockup joke ;-)
so the osg comes as a spool?! or what do you or do they mean with "100%"? every single clutch type lsd will provide full lock and have both wheels spin in the same speed. do you know of any unit that does not do this? the percentage says at what torque difference left vs. right it opens and the wheels begin to rotate at different speeds. so a 100% unit will never open. you would call this a spool! but for a spool the osg seems a little expensive and extremely over-engineered! doesn't it?
and i think you would admit the the osg opens up at a certain torque difference. so the correct locking value is somewhere between 0 and 100 but not 0 and not 100... as any other clutch lsd! the osg website says something different. but well, it is simple physics. or do you have another conclusion or explanation for it?


Quote:
Originally Posted by Billj747 View Post
With doing the above adjustments to make the OSG less aggressive, I have never had inside wheel spin despite driving cars with over 800whp including NA and Turbo: NSXs, 350Zs, 370Zs, M3s, EVOs, RX7s, RX8s, Miatas, Mazdaspeed 3s, S2000s, Boxters, STIs, etc...
i only know and have driven the M3 unit in 2 specs. both were crap. i know that all other people driving osg diffs seem to be happy. maybe these units perform better and/or the drivers never have driven a better unit?!


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Originally Posted by Billj747 View Post
I'll take that as a compliment.
it was exactly meant as this! ;-)
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      11-13-2014, 03:12 PM   #21
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100% lock would mean 100% lock (under acceleration load) like a spool or a detroit locker under heavy acceleration loads since as more load is applied, the clutch plates are squeezed by the ramps. But with the negative preload, this 100% lock is delayed.

Did you see one tire rubber marks from your inside tire when coming out of a corner? Do you have logged data with individual wheel speeds to see the inside wheel spin issue? I'm still very surprised to hear you had on throttle wheel spin issues with the OS Giken since that has not been he experience i've had with them. Without hearing your feedback, I would have thought the off the shelf settings with the negative springs and 5/7 plates activated would be right in the ballpark of where you would want it. I de activated another plate for my NSX which is going to have 500whp and our 800whp racecar has 5/7 engaged like your BMW unit...

60/60 is too aggressive, especially for the decel side ramp angle. I'd honestly put it back to stock. What tires/sizes and power are you running?
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      11-16-2014, 02:08 PM   #22
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Quote:
Originally Posted by Billj747 View Post
100% lock would mean 100% lock (under acceleration load) like a spool or a detroit locker under heavy acceleration loads since as more load is applied, the clutch plates are squeezed by the ramps.
so this is static friction! do you know of any clutch type lsd that has no static friction? this is the normal behaviour of every single clutch type lsd in the world. osg thinks, only their units are able to do that ;-)

commonly, static friction is not described with a percentage as it simply makes no sense! a certain percentage should define the moment when the lsd transfers from static to dynamic friction. this happens due to a certain torque difference left vs. right wheel. if the difference exceeds the %-value of the lsd-setup the clutches break loose. so an open diff has 0% and opens up immediately. a welded or spool hast indeed 100% as it will never open. any clutch type lsd will be somewhere between 0 and 100 depending on the application it is meant for.

would you agree on that?


Quote:
Originally Posted by Billj747 View Post
But with the negative preload, this 100% lock is delayed.
i agree on that.
if this works in real world conditions, it could be a good thing for circuit racing but the downside is it will be harder to predict.
as i did not get the unit to work properly so far i cannot judge over this feature. but it is at least an interesting idea which indeed separates this unit from the competition.


Quote:
Originally Posted by Billj747 View Post
Did you see one tire rubber marks from your inside tire when coming out of a corner? Do you have logged data with individual wheel speeds to see the inside wheel spin issue? I'm still very surprised to hear you had on throttle wheel spin issues with the OS Giken since that has not been he experience i've had with them. Without hearing your feedback, I would have thought the off the shelf settings with the negative springs and 5/7 plates activated would be right in the ballpark of where you would want it. I de activated another plate for my NSX which is going to have 500whp and our 800whp racecar has 5/7 engaged like your BMW unit...

60/60 is too aggressive, especially for the decel side ramp angle. I'd honestly put it back to stock. What tires/sizes and power are you running?
i agree that the 60/60 ramps were too agressive, especially with all clutches activated. i do not like very shallow ramps at all as they make the lsd respond slower and more aggressive. so i will switch back to the steeper ramps with even less lockup on decel (although i normally prefer 2-way setups but osg doesnt have this option with steep ramps at all).

i will leave the neg. preload at 224kg (or even less?) and leave all clutchpacks active but switch back to the spec-s ramps. would you agree that this is a setup that could possibly work?

concerning data logging i would want to have a possibility to have the speeds of the two drivewheels logged or even reported while driving in an acoustic way. quiet while locked, beeping while differentiating. but so far i was only able to read the speeds via inpa software. the wheel speeds are being sent over the canbus. any idea on how to implement a practical solution to extract the data easily and in a useful way?

so i have no datalogging-files of the osg setups but i have loads of experience with lsd units and driving on the limit. so i myself know for sure that the spec-s setup hardly locked at all and the spec-x stayed locked way too long. my measurements on the driving centre one drivewheel on tarmac, the other on slippery surface proofed this.

as i do not get paid but have to pay myself for this testing work, i do not have any official proof of authenticity of course... i only test until i myself am convinced ;-)
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