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-   -   87+ manual transmission destruction, rebuilding, discussion etc.... (https://rennlist.com/forums/928-forum/1089367-87-manual-transmission-destruction-rebuilding-discussion-etc.html)

ptuomov 09-14-2018 04:19 PM

Broadcasting this periodically: If someone has used 87-88 LSD unit in good condition for sale (part number 92833205220), I'm interested in buying it.

ptuomov 09-18-2018 12:22 PM

PING! f someone has used 87-88 LSD unit in good condition for sale (part number 92833205220), I'm interested in buying it.

Mark Anderson 09-18-2018 01:52 PM

We should have one later this week

ptuomov 09-18-2018 03:29 PM


Originally Posted by Mark Anderson (Post 15299461)
We should have one later this week

Let me know what you get. Right now, the most pressing need is for an '87-89 LSD unit.

ptuomov 09-22-2018 05:30 PM

At what measured surface hardness are steel gears usually the toughest in terms of their ability to hold load? 400 Brinell?

slate blue 09-22-2018 06:14 PM


Originally Posted by ptuomov (Post 15309945)
At what measured surface hardness are steel gears usually the toughest in terms of their ability to hold load? 400 Brinell?

I'm no expert, but isn't Brinell used for aluminum and Vickers used for steel, I think one is a ball test the other a point test. I could be wrong...

GregBBRD 09-22-2018 10:45 PM


Originally Posted by ptuomov (Post 15290449)
Broadcasting this periodically: If someone has used 87-88 LSD unit in good condition for sale (part number 92833205220), I'm interested in buying it.

You know the transmission came with a limited slip, right?

ptuomov 09-23-2018 12:32 AM


Originally Posted by GregBBRD (Post 15310552)
You know the transmission came with a limited slip, right?

Rob’s, yes. But I’ve got another one with an open differential.

Wisconsin Joe 09-23-2018 01:04 PM


Originally Posted by slate blue (Post 15310033)


I'm no expert, but isn't Brinell used for aluminum and Vickers used for steel, I think one is a ball test the other a point test. I could be wrong...

I think Brinell is just the 'ball test'. It can be used on a wide variety of materials. I've mainly seen it used on lead (cast bullets).

ptuomov 09-27-2018 11:37 AM

Can anyone identify LSD’s?
 

ptuomov 09-29-2018 06:29 PM


Originally Posted by slate blue (Post 15310033)
I'm no expert, but isn't Brinell used for aluminum and Vickers used for steel, I think one is a ball test the other a point test. I could be wrong...

I read about that and it turns out these gears should be tested using the Vickers or Knoop tests.

"For instance when hardness is checked on a mounted tooth sample, it is typically checked by taking a microhardness traverse. The microhardness is taken either by Knoop, a method using a 500- or 1000-gram load, or sometimes Vickers, using a kg load. Yet nearly all drawings specify surface and core hardness in values of Rockwell "C", a method which uses a 150 kg load. For this reason, a conversion must be made from either the Knoop number or the Vickers number to determine whether the part met the specified Rockwell number. Conversion is not simply a mathematical relationship. Since the structure and cold working properties vary for different materials and hardnesses, The 150kg load used for a Rockwell "C" check is inappropriate to check the hardness close to the surface or elsewhere in the case. This is because the size of the indention made by the 150 kg load homogenize the conditions over a large area. This can mask local deficiencies."


Rob Edwards 09-30-2018 01:37 AM

Greg has a Rockwell hardness tester on a stable table at the shop, but I've never seen him use it on a gear. Not sure which sets of indenters he has nor which sets of hardness scales it can be set up to measure.

ptuomov 09-30-2018 09:33 AM


Originally Posted by Rob Edwards (Post 15327034)
Greg has a Rockwell hardness tester on a stable table at the shop, but I've never seen him use it on a gear. Not sure which sets of indenters he has nor which sets of hardness scales it can be set up to measure.

John Kuhn had some gears measured at a lab, which used Knoop method. The Knoop method is local enough to be useful for gears, while Rockwell C test is not as useful. What's confusing is that the reference values are often quoted in HRC even though they aren't measured with that method.

ptuomov 10-09-2018 10:05 PM

Nothing yet
 
[premature, deleted]

Bigfoot928 10-10-2018 04:46 PM


Originally Posted by ptuomov (Post 15349491)
[premature, deleted]

tease


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