diff gearing

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burky

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I have a 5spd dog box in my CSL, I have an option to go to 373 diff gearing, in the little I have driven my car I thought the gearing was a bit tall , any potential problems, I have a standard LSD.Thanks , Mark.
 
I think that ratio is too high for a dogleg. a 3.07 is what is commonly used with a dogleg. With a dogleg 3.07 is turning about 2500-3000 RPM at highway speeds. Remember a dogleg is direct drive in 5th gear. It is not under driven like in the other 5 speed gear boxes`.. That is where my dogleg runs with a 3.07
 
For the rabbit group in Europe they ran 3.25 diffs with the CR tranny.
I tried it and didn’t like it. Too busy!
 
Agree that 3.25 or 3.07 would be a good fit with the CR box.
I run a 3.45, which is fun on track and in the twisties, but would appreciate a more relaxed ratio if it was a cruiser/long distance tourer.
 
burky said:
I have a 5spd dog box in my CSL, I have an option to go to 373 diff gearing, in the little I have driven my car I thought the gearing was a bit tall , any potential problems, I have a standard LSD.Thanks , Mark.
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3.73 - do you mean 3.63? tall for a CR box? 3.07 might be tall ... 3.45 / 3.63 would be quick and require a lot of shifts. the recommendation of 3.25 is good for a blend of quickness and better highway speeds. the 3.07 is perfect if you drive a lot at highway speeds.
 
I was initially told that the replacement gearing was 373 , but when they showed up they were 363, but unfortunatley the mounting was a 10 hole instead of 8 , I currently have a 325 which I find a bit tall, but at this point I would be happy with a replacement 325 as I have had 2 incorrect gear sets shipped to me.
 
So you are looking for an 8 bolt 3.25 ring and pinion?
And your LSD unit is ok?
 
Yes , thats what I have , slightly lower gearing set wood be great, but I would be happy enough with 3.25 . The person I have been dealing with in Australia still thinks that he can find something for me but I have 2 incorrect sets so far ,I will know around Monday what is happening .Do you have a set ?. I have had no word from the diff shop about the LSD , I will ask the question.
 
I'm about to change from o/d to dogleg box, currently using using a 3.45:1 40% LSD. Suspect I may change to 3:25:1 25% after driving it for a bit. Will sell the diff I don't end up using but that could be a while away given my winter workrate.
 
burky said:
Yes , thats what I have , slightly lower gearing set wood be great, but I would be happy enough with 3.25 . The person I have been dealing with in Australia still thinks that he can find something for me but I have 2 incorrect sets so far ,I will know around Monday what is happening .Do you have a set ?. I have had no word from the diff shop about the LSD , I will ask the question.
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Well- the speed limit in NSW is max 110kph??

"110kph on motorways and freeways."

So- maybe the 3.25 is better with the CR tranny in Oz. In the states the max limit is up to 135kph with many driving above that.
You might end up starting off in 2nd gear like many of us do with CR trannys.!
What you don't want because you will learn to hate it is a 3.45 diff. Like mixing cookie dough all day long...

I have an early (8 bolt, bolt on flange, 3.25 open sideloader) on the shelf.
You could remove the gears and install in your 8 bolt LSD sideloader.

I have a late, slip on flange 10 bolt 3.07 LSD 40% diff on the shelf. Rebuilt and beautiful and ready to go.
and pricy..........

You need to find out if your posi unit was ruined from oil starvation before you do anything?
And I would think your spider gears might be burnt?

Start with knowledge about what you have now.
 
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I’ll be in Sydney on the 27th- arriving Hawaiian Airlines at 7:45 pm.
Let me know if I can help. I can meet the 28th.

i can ship a diff if you need one.
 
Changed- United had a better deal



I‘m in Sydney on the 16th
i have a 3.25 sideloader- maybe fit in my backpack?
 
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I Talked to the person who has been supplying my prior diff gears and he tells me that he has a 3.25 , so I will give this one last shot . The diff shop told me yesterday that the LSD unit looked OK. Thanks for the help and input.
 
Make sure you understand....


Early diffs that came in e9 cars have bolt on flanges and 8 bolt ring gears and LSD units with matching 8 bolts

Later diffs that came on e12 and e24 cars have clip on flanges and 10 bolt ring gears and LSD units with matching 10 bolts.

No swapping parts between early and late....
 
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