NoPistons -Mazda Rx7 & Rx8 Rotary Forum - Need specs / info on JC Cosmo IRS diff's ?

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Need specs / info on JC Cosmo IRS diff's ??

I've spent a few hours on the net !

With a big fat zero ,

I can't find the basics =

Spines , Dia , ring gear size , etc, etc ??????

Did Mazda use something from its RV models or cross shared items with Ford ??

Someone must know something of these diff's ?????

Chip in info people.

Thanks in advance

REgards.

Pete.

13B version

4.3 open standard = series-I

4.3 LSD option = series-I

4.3 LSD standard = series-II

20B version

3.9 LSD standard = series-I + II

Quote:

Originally Posted by Circuit Theory (Post 7321045)

The JC cosmo had two lsd types and final gears.

First being the viscous LSD with a 3.909 final gear

second being the torsen lsd with a 4.3 final gear

Hope that helps.

Quote:

Originally Posted by OLD RX-7 (Post 7323768)

Thanks Tom,

Much appreciated ! :icon_tup:

That does help as the types of LSD's the cosmos have.

Still would love to know the rest ( Spines , Dia , ring gear size , cross shared ? )

The diff crown wheel ( ring gear ) size is much bigger than RX-7 S5/6/etc !

Anyone with a workshop / technical diagrams of the rear diff please forward them to my e-mail addy ( oldrx-7@tpg.com.au )

Thanks again.

Regards.

Pete.

Still need info,etc !

Thanks.