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El Patrick

Did LSD come standard on the 986 Boxster?

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I did a search here on the forums but couldn't find exactly what I was looking for.

Did the 986 Boxster come with an LSD as a standard feature? I'm in the market right now for a 986 Boxster so I was just wondering. I'm looking at a 1997 and a 1998 and a 1999 so I'm really wondering about those model years in perticular. I find it kind of hard to believe that a Porsche would not come with an LSD, but I just want to make sure.

Thanks for the help! :renntech:

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I did a search here on the forums but couldn't find exactly what I was looking for.

Did the 986 Boxster come with an LSD as a standard feature? I'm in the market right now for a 986 Boxster so I was just wondering. I'm looking at a 1997 and a 1998 and a 1999 so I'm really wondering about those model years in perticular. I find it kind of hard to believe that a Porsche would not come with an LSD, but I just want to make sure.

Thanks for the help! :renntech:

If you are limiting your search to 1997, 1998, and 1999, be aware that those three first years all had the "version A" transmissions for the convertible top, which are generally more trouble-prone than later models.

Some of those may have already had their convertible top transmissions replaced with the "version B" (i.e., non-half-moon gear) at some time during their service life.

Just a heads up.

Regards, Maurice.

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No 986 Boxster's have limited slip differentials, but they can be added.

Edited by rick3000

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Hi Patrick,

Maybe you are mistaking P37 $867 $678 Traction Control with ABD (Active Brake Differential) for LSD.

Just a thought, check out this site http://www.986faq.com/default.asp for all options available on the 986.

My opinion if you are looking to buy a 1997-1999 Boxster, choose one with the least millage and minimum electronic gadgets and get it checked by a

Professional that has worked on these cars and has an idea where to search for weaknesses.

Just my honest 2 cents.

Good luck.

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Hi Patrick,

Maybe you are mistaking P37 $867 $678 Traction Control with ABD (Active Brake Differential) for LSD.

Just a thought, check out this site http://www.986faq.com/default.asp for all options available on the 986.

My opinion if you are looking to buy a 1997-1999 Boxster, choose one with the least millage and minimum electronic gadgets and get it checked by a

Professional that has worked on these cars and has an idea where to search for weaknesses.

Just my honest 2 cents.

Good luck.

Did you know RennTech.org has a full option listing for most Porsche's?

It is located here

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Hi Patrick,

Maybe you are mistaking P37 $867 $678 Traction Control with ABD (Active Brake Differential) for LSD.

Just a thought, check out this site http://www.986faq.com/default.asp for all options available on the 986.

My opinion if you are looking to buy a 1997-1999 Boxster, choose one with the least millage and minimum electronic gadgets and get it checked by a

Professional that has worked on these cars and has an idea where to search for weaknesses.

Just my honest 2 cents.

Good luck.

Did you know RennTech.org has a full option listing for most Porsche's?

It is located here

Hi Loren,

The reason i gave another site was because Patrick mentioned "I did a search here on the forums but couldn't find exactly what I was looking for."

Sorry

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Yeah, well I did a search in the 986 forum for LSD Limited Slip Differential. I couldn't find the exact answer I wanted so I made a new post. I didn't know about the options page, but that still wouldn't have answered my question if Boxsters came with an LSD standard. Anyway, thanks for the help everyone!

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Quaife has a torque biasing differential for the Boxster, but I haven't heard any reviews. If you check out the Boxster racing forums they may have some more info on them.

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For street use, with the standard Boxster HP, a LSD just isn't necessary. Helpful if you track the car, but again, we aren't talking a whole lot of power here.

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LOL, I'm sorry.... but everytime i see this post on the list.... it pops up next to the "Getting High" post, and I just have to chuckle... perfect timing ;)

:cheers:

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LOL, I'm sorry.... but everytime i see this post on the list.... it pops up next to the "Getting High" post, and I just have to chuckle... perfect timing ;)

:cheers:

:lol:

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986 Boxster had optional LSD, certainly for MY2000. Option Code 224:

M224 AUTOMATIC LIMITED SLIP DIFFERENTIAL

:welcome:

That was actually part of PSM and an "electronic/hydraulic" form of LSD. Not a real LSD (which is mechanical) PSM's electronic/hydraulic version brakes the slipping wheel.

In PSM descriptions (not the option list) is is more accurately called ABD - Automatic Brake Differential - A traction control program which works in conjunction with the new ABS/5 brake system. The ABD is active up to 45 mph. The system applies brake pressure to the rear wheel with the least amount of traction.

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Thanks for the explanation :)

So does it mean this car comes with PSM?

0004.jpg

986 Boxster had optional LSD, certainly for MY2000. Option Code 224:

M224 AUTOMATIC LIMITED SLIP DIFFERENTIAL

:welcome:

That was actually part of PSM and an "electronic/hydraulic" form of LSD. Not a real LSD (which is mechanical) PSM's electronic/hydraulic version brakes the slipping wheel.

In PSM descriptions (not the option list) is is more accurately called ABD - Automatic Brake Differential - A traction control program which works in conjunction with the new ABS/5 brake system. The ABD is active up to 45 mph. The system applies brake pressure to the rear wheel with the least amount of traction.

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As I recall they did not offer PSM on the Boxster until MY2001.

Looks like you got TC (Traction Control). Do you have a button on your dash that says "TC"?

post-1-1240028706.jpg

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Yeah, well I did a search in the 986 forum for LSD Limited Slip Differential. I couldn't find the exact answer I wanted so I made a new post. I didn't know about the options page, but that still wouldn't have answered my question if Boxsters came with an LSD standard. Anyway, thanks for the help everyone!

I found it hard to believe as well, until i dug a little deeper.

Turns out, theres this option for something LIKE a LSD...

on cars with the stability management option, apparently the computer already has alot of control over the brakes.

so what it can do is take constant measurements of both rear wheels, and apply a tweak of brake to the spinning one.

on a conventional open differential, this makes more torque goto the other wheel.

it does this so fast and so well, if you dump the clutch (with PSM off) it will leave two black marks... if you have one wheel off in the sand and the other on the road, you wont get stuck, etc...

but heres the nicer part.. at higher speeds, (45mph according to Lorens post above) it doesnt do it.. so you can get the excelent high speed cornering of an open diff, while still being able to snap the back around with the throttle when autocrossing... just like a LSD.

add to that, the open diff weighs less..(and its rotating mass) and the system adds no weight, as the hardware already must exist for the ABS... it becomes a software-only upgrade at that point.

its a very cool little feature.

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Yeah, well I did a search in the 986 forum for LSD Limited Slip Differential. I couldn't find the exact answer I wanted so I made a new post. I didn't know about the options page, but that still wouldn't have answered my question if Boxsters came with an LSD standard. Anyway, thanks for the help everyone!

I found it hard to believe as well, until i dug a little deeper.

Turns out, theres this option for something LIKE a LSD...

on cars with the stability management option, apparently the computer already has alot of control over the brakes.

so what it can do is take constant measurements of both rear wheels, and apply a tweak of brake to the spinning one.

on a conventional open differential, this makes more torque goto the other wheel.

it does this so fast and so well, if you dump the clutch (with PSM off) it will leave two black marks... if you have one wheel off in the sand and the other on the road, you wont get stuck, etc...

but heres the nicer part.. at higher speeds, (45mph according to Lorens post above) it doesnt do it.. so you can get the excelent high speed cornering of an open diff, while still being able to snap the back around with the throttle when autocrossing... just like a LSD.

add to that, the open diff weighs less..(and its rotating mass) and the system adds no weight, as the hardware already must exist for the ABS... it becomes a software-only upgrade at that point.

its a very cool little feature.

this post was awhile ago, but wanted to add a bit more info incase someone else is looking.

For 986 Boxster 1997-1999 with "Traction Control" (prior to PSM 2000-2004)

What Porsche had done with their traction control option is give you something

that works similar to a "limited slip differential" but is really the "ABD" automatic

braking differential.

According to some of my very early 911/Boxster (1997-1998) Porsche brochures and my own experience with

my 98 Boxsters Traction control "ABD" automatic braking differential .... this is how it works in a nutshell.

Included in "Traction Control" is the "ASR" anti slip regulator, and "ABD". If one tire slips the automatic brake differential applies the brake to

the slipping tire, hence reacting and behaving just like a limited slip differential. If BOTH tires spin, then the ASR slip regulator

kicks in and retards the ignition and cuts power so that traction is regained.

Even when Traction Control is turned OFF.... ABD will still react up speeds of 45mph or 62 mph with PSM

For the 996 and 2000-2004 boxsters this is how it works with PSM

PSM Porsche stability Management while ON uses ABS, anti-slip regulation, an automatic brake differential and a battery of sensors

that monitors direction, pitch, speed, yaw velocity, and lateral acceleration. It will apply the brakes to individual wheels in order

to stabilize the vehicle based on what kind of slide/skid the car is in.

Included in PSM is also the ASR anti slip regulator, and ABD. If one tire slips the automatic brake differential applies the brake to

the slipping tire, hence reacting and behaving just like a limited slip differential. If BOTH tires spin, then the ASR slip regulator

kicks in and retards the ignition and cuts power so that traction is regained.

Turning PSM OFF will disable the ASR, four corner braking montiors, and pitch/yaw sensors...... BUT the Automatic braking differential stays on at ALL times

up to 62 mph... That is why you will notice that even with the PSM OFF light showing you will still see a separate flashing warning light letting

you know that ABD is still kicking in during certain rear traction sliding situations to try and behave like a limited slip differential....

Hope this makes sense. It is pretty amazing programing that Porsche has developed. But nice to know you can turn it off if you are brave enough ;^)

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So, I did a short little heater with my Boxster S - the results

319085_2280190800537_1121810035_32712733_5675470_n.jpg

no peg leg . . . . does this mean the car has an LSD or was the distance too short?

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A real check for a mechanical diff is to lift the rear, and rotate a wheel. If the other wheel rotates too, but in the opposite direction, then it has a mechanical locking diff.

I added a Guards 60/40 LSD to my 986S racecar. There are certain turns at certain tracks with poor rear grip (Homestead Miami Speedway for example) where the LSD kicks in a lot. The Boxster race cars in the Grand Am Sports Car Challenge ST Class are also using this same diff.

If anyone else is thinking of adding a diff for track use, the Grand Am guys tested both the 80/20 and the 60/40. The 80/20 caused excessive understeer. The 60/40 also makes it biased to understeer, but it can be dialed out with shocks, springs and sway bar settings.

If anyone is thinking about a diff for spirited street driving, the torque biasing diffs are good.

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