Axle ratio change in VR V8 auto

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Coretuned
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Axle ratio change in VR V8 auto

Post by Coretuned »

Hi all, I need to change the axle ratio code in engine and trans for a VR V8 auto. The calculation is
(tyre rev's per km X diff ratio)/.0352
(From memory I think that's the division number)
I calculate the info and get a large number in the 10s of thousands.
The number currently is 0.0232 in the axle code.
I'm not sure what I'm doing wrong.
Tyres are 235/45/17 and 3.45 diff gears. This is the ratio I need to update it to.
Then after that I will work out shift point adjustments.

Thanks guys.
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antus
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Re: Axle ratio change in VR V8 auto

Post by antus »

try applying it as a percentage change from stock. So say your ratio is 10% larger than stock then revolutions are 10% less, so multiply the existing value by 0.90, or if the ratio is 10% less multiply the value by 1.10 etc.
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