Will it be a pig to get moving from a standing start Byron.
If not, i'd be interested in the spreadsheet as well.

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My only concern is that i once blew up a M21 behind a worked 308, and all i did was change back from 4th to 3rd doing 40km/h.
I was easy on my ute as it had a 6cyl banjo diff in it and i never even damaged an axle or diff gears. So i'm easy on vehicles.