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Author Topic:   LIMITED SLIP FOR METRIC
LMS53
Dirt Roller

Total posts: 23
posted October 19, 2005 06:35 AM  
DOSE ANY BODY HAVE A LIMITED SLIP REAR END FOR A METRIC CAR OR WHERE I CAN FIND ONE WHAT KIND OF CAR?

magician227
Dirt Full Roller

Total posts: 60
posted October 20, 2005 04:42 PM  
LM,

Metris spools are quite expensive. The most common way of locking your rear end is to just weld the spiders together. Is really simple, remove your cover and drain. Clean everything really good with brake cleaner. Make sure all lube, grease, and brake cleaner are gone. Just tack weld the spider gears in 3-4 places and you are locked. If you must have a spool, they are out there. Check Speedway or Scroggin-Dickey. But they do cost about 3 times as much as a mini-spool for a 9in.

Magician

LMS53
Dirt Roller

Total posts: 23
posted October 20, 2005 04:59 PM  
thanks for the info. but i was looking for an oem rear end spool. positrac or something like that. that will bolt in as stock replacement. can't run a locked rear end. has to be stock.

Normal Sullivan
Dirt Full Roller

Total posts: 58
posted October 20, 2005 09:09 PM  
I thought some of the buick turbo/grand national or hurst/olds cars came with a limited slip differential...

magician227
Dirt Full Roller

Total posts: 60
posted October 20, 2005 11:14 PM  
The Grand Nationals and GNX's did have posi units. Good luck finding one of those in your local s**** yard. I think the SS Monte's also had a posi option. Just a question, I would think that no locked rear would rule out ANY form of limited slip. How could they check if you had a factory posi, or a welded spider. I would not think they would pull a diff cover.....awful messy.

Magician

LMS53
Dirt Roller

Total posts: 23
posted October 21, 2005 04:04 PM  
they have had us pull our thrid member before on our pro stock. so just pulling a cover I wouldn't put it past them. they say as long as it is a stock oem part we can run it. there are some cars last race that looked like they had a locked rear end. if a posi is too hard to find then I'll do something else. thank for all the info.



Eljojo
Dirt Forum Champ
Total posts: 987
posted October 21, 2005 05:13 PM  
Isn't there a way to shim the spiders so tightly that, altho they aren't welded they still won't turn? I don't know, but seems like I have heard that.

Raceman17
Dirt Maniac

Total posts: 177
posted October 25, 2005 08:48 AM  
Yes you can shim up the spider gears up. You need to get an extra set of spacer washers (the curved one that go on the back of the spider gears) and grind the lip of the inside edge. You have to use a die grinder or something like that to get the rasied edge off. Once you get that done, take the rearend apart and use the original spider washers with the new washers that have the edge removed and place the set behind each spider gear. You have to roll the spacers in place and it is a pain to get it done. If the rearend is out of the car it is easier but, it does take time and patience. THEY WILL GO IN THERE as long as you can roll them in (you have to do both sides at one time) Whats good about this set up is that you can check the rearend by jacking up on tire and it will still roll (meaning it is not locked) once the fluid get hot, it will expand the washers and lock the rearend. I have ran my car like this for years with no problem.
Later

hotrodenford
Dirt Full Roller

Total posts: 68
posted October 25, 2005 12:06 PM  
I am building a 1980 regal for next year. it has the original rearend and gears. I don't plan to change the ratio. I have a factory posi unit to put in it. I also have shims out of old axels. Which option would be better? how many laps does it take for the shim option to lock up on a 1/4mi low banked oval? I would rather not weld the gears together, I have had them brake before. our rules alow any diff type.

outlaw#03
Dirt Roller

Total posts: 25
posted October 25, 2005 02:43 PM  
The "chunk" out of a late model Camero or Firebird should a posi track and they will a 7.5" housing, But you have to order 28 spline axles form Mosier.

Raceman17
Dirt Maniac

Total posts: 177
posted October 25, 2005 07:25 PM  
quote:
Originally posted by hotrodenford:
how many laps does it take for the shim option to lock up on a 1/4mi low banked oval? I would rather not weld the gears together, I have had them brake before. our rules alow any diff type.

If you get both sets of washer in the rear end it will be pretty tight. (some people can only slip one in) It wont take long to lock up with the friction and heat in the rearend. I would not weld it. But if you do just take the larger gears out and weld one gear tooth up then skip one and weld the next one up. Do this on both sides. Then you can jam the spider gears between the two welded teeth. This also works and you dont ruin the whole rearend.
Later


racer17j
Dirt Forum Champ
Total posts: 5448
posted October 29, 2005 08:34 AM  
quote:
Originally posted by hotrodenford:
I am building a 1980 regal for next year...I have a factory posi unit to put in it. I also have shims out of old axels. Which option would be better?

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If it has wheels or a skirt, you can't afford it! But they shure are fun...

bigdozer
Dirt Full Roller

Total posts: 54
posted November 04, 2005 11:21 PM  
buy the locker for about 80 bucks and be done.

racinrob
Dirt Roller

Total posts: 5
posted November 14, 2005 05:37 PM  
82 and newer Camaros/Firebirds, S-10's (especially 4wd), and Astros are your best sources for OEM 7.5 posi rears. You just have to watch your pinion bearings and splines. Some of the pre-80 rears used a different pinion bearing and your 90 and newer rears will be 28 spline (the older ones are 26 spline. You can usually find some listed on Ebay.

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2003 Path Valley Speedway 6 cyl. Strictly Stock points champion
Winner of 1st Annual 50 Lap Strictly Stock Special, V8 division

Champ2x36
Dirt Full Roller

Total posts: 38
posted November 27, 2005 07:05 PM  
How many shims do you use on each side? Are there different thicknesses of the shims? I'm considering building my wife a pure stock for next year, and the rules don't allow any locked diffs or posi units. I had not heard of locking the diff with extra shims behind the side gears before.

Ed

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When the drops the stops!!

My website: www.geocities.com/champ2x36

[This message has been edited by Champ2x36 (edited November 27, 2005).]

James Ott
Dirt Maniac

Total posts: 151
posted November 27, 2005 07:31 PM  
Raceman when you say the larger gears you mean the splined ones? Correct?

Raceman17
Dirt Maniac

Total posts: 177
posted November 28, 2005 06:52 AM  
Yes if you are going to weld it up use the two outside larger gears (like you said the one's with shims)

For Champ2x36:
The shims I am talking about are the two curved shims that sit on the back of the smaller gears (the ones that are about 1.25" in diameter) If you take the rearend apart, these gears are the ones that are held in place by the long pin. You will need a pair behind each gear. You will have to remove the inside lip from the outside shim so it will rest against the other shim. Like I said before, IT IS A PAIN TO DO THIS ON YOUR BACK UNDER A CAR so it really helps if the rearend is out of the car. It also takes patience to get the shims in there because it was only designed for one shim in each side. Its tough to do it but once you get it in there, that booger will be locked. Hope this helps
Later

Champ2x36
Dirt Full Roller

Total posts: 38
posted November 29, 2005 01:27 AM  
Thanks, Raceman17. I had never heard of this before, but it is definitely good to know. Gotta go diggin' thru the garage, I put a mini-spool in one of these diffs several years ago, I wonder if the spiders and side gears and shims I took outta that one are still in the junk in the garage, if so that would supply the extra set I would need.

Ed

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When the drops the stops!!

My website: www.geocities.com/champ2x36

Raceman17
Dirt Maniac

Total posts: 177
posted November 29, 2005 06:54 AM  
You can also pick up a set at the GM parts house. I have got a set of them there before for a few bucks.
Later

Champ2x36
Dirt Full Roller

Total posts: 38
posted November 29, 2005 12:01 PM  
Raceman17,

When you say GM parts house do you mean the local dealership, or some other company, or website?

Thanks,
Ed

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When the drops the stops!!

My website: www.geocities.com/champ2x36

Raceman17
Dirt Maniac

Total posts: 177
posted November 29, 2005 12:15 PM  
GM dealership (true gm parts)
Later

Raceman17
Dirt Maniac

Total posts: 177
posted November 29, 2005 12:42 PM  
The part you are looking for is called a differential pinion thrust washer. They can be found on the internet. The gm part number is 559291 (this is for a 7.5" gear with a 3 character axle code). They other number is 344167 (this is for a 7.5" gear with a 2 character axle code). Dont ask me about the character code because I dont know whats the difference between a two and a three. I'm guessing one is a locker and the other is not. Call gm and give them these numbers. Tell them you have the non locking differential. They should be able to go from there. If not, they need to find a new job. Hope this helps.
Later

john56h
Dirt Newbie

Total posts: 2
posted December 04, 2005 02:49 PM  
Carful with tech. All the tech man has to do is take a tire marker before the race and make a mark on the tire on both sides of your car (say 12 o'clock) and after the race they shouldn't line up anymore if it's an open rear. Easy for them to get an idea who's running locked without pulling rears. Of course there's a chance it could end up back lined up, but pretty unlikely. Usually if you swear to them that it's open, then they'll go to the trouble of pulling the cover to be sure.

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