Garages that could upgrade the diff
Discussion
I have a 3.91 diff in my CV8, cant really tell you how much difference it made as it has always been in there, I can say 70MPH in 6th = about 1500 RPM from memory. on 19" 245x35x19
I do also remember some time back Monkfish saying pound for pound changing the diff ratio to a 3.91:1 on a CV8 was the best performance upgrade you could buy.
As word of caution however the after market 3.91 crown wheel and pinions have a reputation for being noisy (whiny), try to get a OEM one if you can as these are quieter (mine is pretty quite).
Also when you have it apart if budget allows swap the LSD to something better than the OEM one. (Truetrac or a Wavetrac). I have had a Truetrac from 10 plus years no issues so far and definitely an improvement over the stock one.
And finally if money is no object get the Harrop diff cover as they get pretty hot even with the cover.
Very old thread on the subject
https://www.pistonheads.com/gassing/topic.asp?h=0&...
I do also remember some time back Monkfish saying pound for pound changing the diff ratio to a 3.91:1 on a CV8 was the best performance upgrade you could buy.
As word of caution however the after market 3.91 crown wheel and pinions have a reputation for being noisy (whiny), try to get a OEM one if you can as these are quieter (mine is pretty quite).
Also when you have it apart if budget allows swap the LSD to something better than the OEM one. (Truetrac or a Wavetrac). I have had a Truetrac from 10 plus years no issues so far and definitely an improvement over the stock one.
And finally if money is no object get the Harrop diff cover as they get pretty hot even with the cover.
Very old thread on the subject
https://www.pistonheads.com/gassing/topic.asp?h=0&...
mind you If I fitted one I might have to fit rear air shocks to jack the back end up and show it off 
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