HELLO FELLO THIRD GEN LOVERS,

I HAVE A 90 IROC THAT CAME STOCK WITH 2.73 GEARS. I AM SWITCHING TO A 3.23 GRAR RATIO, AND WOULD LIKE TO KNOW HOW TO CALIBRATE THE TRANS FOR THE NEW GRAR RATIO. I SEE POSTS FOR CARS WITH A CABLE, BUT MY CAR HAS THE ELECTRIC GUAGES AND NO CABLE. I DID A SEARCH AND DIDN'T FIND ANYTHING. ANY HELP WOULD BE AWESOME!!!!

 

There's a tech article on this. You need new speedo gears, both in the speedo housing and on the tailshaft of the tranny.

 

I think you only need to swap the gear at the sensor. when i swapped my 2.73 for a 3.27 in my 91 rs i only changed the one behind the sensor if i remember correctly.

its the same for the electric sensor as the cable one. Just pull the sensor from the tailshaft and r/r the gear.

 

if you go to your GM dealer thay can get you the gears.. you will more than likely need both of them.. I have a trans that was set with the 2.73 gears and it is in my 3.08... just changed the housing gear and not the one in the trans it i am not about 4mph off (I do 35, laser says 39)... So i would definitely go and hcek the dealer. they can run the ratio for you in like 5 minutes. and changing the one in the tail housing is a breeze anyhow.. just have to take the driveshaft off. remove the tail housing, and you are looking right at it. and there is not gasket for the tail houseing.. I used the Black RTV on another trans without any problems

 

HEY ALL,

THANKS FOR THE RESPONSES, I REALLY APPRECIATE IT!!!!!!