I am preparing to change out the rear gear from the stock 3.23 to a 3.73. Its an A4 345hp SS that i just bought.
My questions are: 1) I need to recal the speedo which I understand.
2) the real concern I have is with the auto tranny...I have been told that I will need to change the shift points so as to keep from banging the rev limiter, and also wouldnt it be appropriate to up the rev limiter a tad since going to a steeper gear?
3) would the hypertech programmer be the tool of choice?
appreciate any inputs from anyone....and sorry for the length of message.

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69 Rally Sport Z/28 Cortez Silver-- unmolested original car

2002 Limited Edition SS conv, A4 345hp

 

I too changed my gears and I used the Hypertech Power Programmer III to recalibrate my speedometer. My shift points were kinda out of whack to begin with even before the gear change, so I'd definitely mess around with those. Some people discourage against raising your engine rev limiter, but I did upon viewing other people's setups on this message board and by the suggestion of a Hypertech Tech. Here's my current setup that I've found the best performance out of thus far:

Engine Rev Limiter - 6500 rpms
1st-2nd shift - +2 (mph)
2nd-3rd shift - +2
3rd-4th shift - +3

My only experiences are with the Hypertech, and it's been pretty helpful so far with the mods I've done. It is very pricey, so I'd also look into LS1 Edit or some other computer programmer. Hope I helped you out.

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1998 Z28 (A4)
Granatelli Airbox Lid,
K&N Filter,
Granatelli MAF Sensor,
160* Power Stat,
Hypertech Power Programmer III,
NGK TR-55IX Spark Plugs,
Taylor 8mm Wires,
Fast Toys Ram Air,
SLP Strut Tower Brace,
Vigilante Torque Converter (3200 stall),
Richmond 3.42's (from stock 2.73's),
Summit Rear End Girdle,
Gutted Cats,
O2 Simulators,
Flowmaster Cat-back Exhaust,
Nitto Drag Radials

 

I too changed my gears and I used the Hypertech Power Programmer III to recalibrate my speedometer. My shift points were kinda out of whack to begin with even before the gear change, so I'd definitely mess around with those. Some people discourage against raising your engine rev limiter, but I did upon viewing other people's setups on this message board and by the suggestion of a Hypertech Tech. Here's my current setup that I've found the best performance out of thus far:

Engine Rev Limiter - 6500 rpms
1st-2nd shift - +2 (mph)
2nd-3rd shift - +2
3rd-4th shift - +3

My only experiences are with the Hypertech, and it's been pretty helpful so far with the mods I've done. It is very pricey, so I'd also look into LS1 Edit or some other computer programmer. Hope I helped you out.

------------------
1998 Z28 (A4)
Granatelli Airbox Lid,
K&N Filter,
Granatelli MAF Sensor,
160* Power Stat,
Hypertech Power Programmer III,
NGK TR-55IX Spark Plugs,
Taylor 8mm Wires,
Fast Toys Ram Air,
SLP Strut Tower Brace,
Vigilante Torque Converter (3200 stall),
Richmond 3.42's (from stock 2.73's),
Summit Rear End Girdle,
Gutted Cats,
O2 Simulators,
Flowmaster Cat-back Exhaust,
Nitto Drag Radials