Speedo help.

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Oct 27, 2018 | 05:31 PM

Swapper

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From: Van Nuys, CA

Speedo help.

dunno if this is the right section or if i should put this in the conversion section but ill ask either way. i have a 95 s10 that now has a 5.3/ t56 swap in it. i am having issues getting the speedo to read sorta close to what it should be. when i bought the truck it had a lt1 and the same exact t56 thats still in it now. (i converted it from LT to LS). when it was LT the speedo read correctly but now it is way off. i have tried adjusting with the tire size wizard and changing gear sizes in hptuners but it doesn't change much. I'm guessing its something in the vss pulse or something like that.

weird thing is my gauge is reading exactly what the PCM is reading. so if i hook up my hptuners and drive it itll say like 24 mph on hptuners and on my cluster but ill be on the highway doing 65-70ish.
i wan tot buy a gauge thing like the edge cts2 but i feel like itll still read wrong.

tire size is a 275/40/17
unknown rear gears. (RPO codes says 4:10 but i highly doubt it)
lt1 t56 converted to ls1 t56.

any help is greatly appreciate and if this is the wrong section please move.

also heres a pic of my "speedo settings"

Oct 27, 2018 | 09:56 PM

truckdoug

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From: Portlandia

go into the tire/gear wizard and change your tire diameter and gear ratio....probably no concern for you but be aware this adjusts shift points for auto trannies

if that doesnt help lmk i think there's a way to change the pulse output. might be p59 blue/green computers only