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Aug 15, 2018 | 02:19 PM

#21

Crackerbuzz

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Thanks for the info Doug, I will start investigating.

Cheers

Aug 15, 2018 | 07:35 PM

#22

ronbros

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From: Austin tx and Daytona FL.

Quote:

Originally Posted by Doug

I used a GM adapter #1565208. You'll have to find a used one. BUT, actually, you'd first need to calculate the amount of correction you need in your application and work from there.

The local NAPA auto parts store helped me with the drive pin dilemma....but I'm on my first cuppa coffee so the details are a bit fuzzy at the moment. I'll report back.

You definitely need a angle drive adapter. Not enough room between the transmission and the transmission tunnel for a straight one.

A slight PITA, yes....but it's all doable. Tons of stuff and info out there to correct speedometer readings. Here's just one example:

800 Series Speedometer Drive Train Correction Adapter

Cheers
DD

i use an angle adaptor, brought it to a speedo shop to chassis dyno and calibrate speedometer, only charged me $60 bucks. all is good .

Aug 16, 2018 | 02:26 PM

#23

Crackerbuzz

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Another tech question...

Does anyone know if the 1984 HE V12 came out with optional LSD or Open variations or were they ALL LSD?

And I am presuming 2.88 was the only ratio offered in the 12?

Cheers guys

Aug 16, 2018 | 02:34 PM

#24

ronbros

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From: Austin tx and Daytona FL.

Quote:

Originally Posted by Crackerbuzz

i'm quite sure ALL XJS had LSD diffs. my 1978 XJS had 3.07 ratio LSD ,so Jeep gears fit right in,3.73

Aug 16, 2018 | 08:18 PM

#25

Doug

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From: Pacific Northwest USA

Quote:

Originally Posted by Crackerbuzz

As Ronbros said, all XJSs have LSD.

When the HE engine was introduced mid-1981 the 2.88 ratio was standardized across the board for all markets. I don't think you could order a different ratio even if you wanted one

Prior to that 3.07 and 3.31 were the usuals, depending on year and market. I think USA market cars had 3.31 until 1979-80 or so. After that, 3.07....which I think was standard issue for most other markets

Cheers
DD

Aug 17, 2018 | 06:17 AM

#26

warrjon

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From: Vic Australia

I replaced my gears with 3.58 out of an XJ40. used the whole LSD centre, had to hybrid slightly to keep the diff speed sensor. The difference in acceleration is very noticeable.

Another option is to buy the gears and have a spacer machined to fit between the crownwheel mounting flange. this has been done successfully in at least 2 XJS race cars here in Australia.