I currently have a 6hp 2.73std rear axle. i'm thinking about upgrading to an 8xx3.70posi rear axle out of an 86. i was wondering, to make the speedo work correctly, would i need to swap the vehicle speed sensor located on the transmission housing (automatic). i was wondering if this would correct the spedometer? any input is appreciated.

 

yup,

some poeplw will say watch out but as long as the donor car is a bird your good, if its a camaro, the speed sensor is strill gear driven and wont work for shizzle.

 

IIRC, the 86 firebird still had the mechanical speedometer. If so, you'll need the VSS from your transmission, and you'll need to get the correct gears.

 

nope. my 86 trans am has the electroic speedo, soooo. ummm yeah.

 

So he'll only need the gears then.