EFIDynoTuning Forum

ok, i'm pretty much a newb at this trans tuning stuff. so pls some advice?

i'm running RZASA on a '03 2V 4.6 CVPI w/4R70W (or 4R75W?) in an ~4000lb 1971 F250 (shortbed camper special), D60 3.73 gears. i've been dialing in the tune recently thanks to Decipha making hardware attainable again.

most everything is pretty good except for ONE NAGGING PROBLEM....the damn 4-3 kickdown, and subsequent 3-2 kickdown that follows while at fwy speeds (70-80mph). not good.

i've got the upshift speeds set, TCC lockup/unlock speeds set, max MPH in 3rd, 2-1 pullin max and 3-2 pullin max, all set reasonably low. and below freeway speeds she shifts like a champ! (edit: also set the gear ratio, did all the maths for the OSS/VSS, tire size, etc etc)

i just can't wrap my head around how the 4-3 shift and 3-2 shift tables function. pls explain the TP_REL vs MPH, is it over or under defined MPH for kickdown? and how can i completely disable the 4-3 shift above like 75mph?

thanks, sorry probably stoopid question, can someone pls splain me?

at that tprel you need to be at or above that mph for the shift to be commanded

and for downshift at that tprel you have to be at or below that mph for the downshift to be commanded

thanks man! yeah, i just figured it out. did a test by setting everything above 30% TP_REL to 35mph on the 3-2 and viola! no kickdown.

now i just gotta dial it in. thanks for the reply! learning.. learning..

vintagespeed wrote: ↑2024 Jun 19, 19:24...how can i completely disable the 4-3 shift above like 75mph...

to answer my own question for the posterity of others who may be suffering same problem.

to completely disable the 4-3 kickdown above 75mph, you would pick a TP_REL (say 40%) and set everything above that to 75mph all the way up to 100% TP_REL. so above 75mph it will never kickdown to 3rd.