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Diff Ratio BJ7

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Tassiedave

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Can anyone advise what the original diff ratio would have been for a BJ7. Is there any way to tell what the ratio is without removing diff.
When i purchased the car i was told that it had been fitted with a Longer ratio diff which suits me well, but I have to replace the crown wheel and pinion and would like to purchase parts before pulling diff out.

Thanks

David
 
Hello David, I'm pretty sure that the BJ7 had a 3.90:1 rear gear from the factory. That's what mine had in it when I changed it out for a 3.54:1 ring and pinion. If you want the tall legs for your car you might as well buy a 3.54:1 ring & pinion now because I believe that is the highest ratio available for the Healey. :cheers:
 
Agree with Vette but there is no way to be sure without pulling the diff. Based on what the PO said it might already have a 3.5 Get an accurate speed reading at 3000rpm and compare with somebody who has a 3.5. I'm sure some forum members could give you their speeds to compare
 
Non overdrive cars had 3.54:1 ratio.
 
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