shifting issues with ls1 edit
shifting issues with ls1 edit i tried to check past postings cause i just cant believe i am the only one with this problem, but i didnt see any so give some help!!!! i have a 2000 T/A i changed rearend to a 4.10 from a 2.73. i tried a hypercrap tuner to adjust my shift points and ran into a problem. if you set the 1-2 shift at 2mph over and set 2-3 shift at 4 or 5 mph over, then it skips 2nd gear and goes into 3rd. if you set 2-3 shift at 6mph then it will hit second, but it also hits rev limiter set at 6600. so i scrapped the hypercrap and had a buddy install ls1edit. well we ran into the same problem. i dont understand why it ask for a rpm and a mph if it will only go by the mph, and whose brite idea was it at GM to set shift points at mph and not rpms. that just seems silly to me. has anyone else seen this problem and what was the fix. also i noticed that we set the 2-3 shift point at 64 mph but the speedo reads about 72 when it shifts. and for the gurru's of tuning, can i use ls1edit for my all my tuning and then use the hypertech to set my shift points. are the 2 actually different softwares they are writing to the computers or are they just used to hack into the GM software and any of them will work together?
no one wants to give any knowledge on this? or does no one know wtf im talking about. i was watching another thread about a similiar problem and i seem to know what everyone else knows. are there no tuners on this forum? is this an unfixable problem? surely not!
TECH Senior Member
Joined: Nov 2001
Posts: 7,036
Likes: 1
From: Lake Zurich, IL
the PCM uses both RPM AND MPH to shift... both conditions must be met in order to shift (you must be at a certain MPH and past a certain RPM)
If you want to shift by RPM, then set the MPH low and the RPM about 100-200 RPMs short of where you want to shift and it'll shift by RPM
As for using the hypercrap over an edit tune... not sure if it would work ... if you apply the hypercrap power tune then it's going to overwrite data... but just changing shift points I'd imagine it'd be fine (you'd want to first remove all HPP3 settings from your PCM, then reconnect to it so that the hypertech re-reads your newly modified PCM , that way the flash file it stores internally matches your new base settings)
As for the lack of replies... several probably opened the post and then just closed it as your original post is kind of hard to read (puncuation and paragraphs would make it easier)
As for why you're hitting the rev limiter or why the speedo is off... you need to verify that what you entered into edit is correct... tire height and rear gear ratio...
Also would be helpful if you could post what you set the RPM and MPH limits to in the WOT shift tables...
If you want to shift by RPM, then set the MPH low and the RPM about 100-200 RPMs short of where you want to shift and it'll shift by RPM
As for using the hypercrap over an edit tune... not sure if it would work ... if you apply the hypercrap power tune then it's going to overwrite data... but just changing shift points I'd imagine it'd be fine (you'd want to first remove all HPP3 settings from your PCM, then reconnect to it so that the hypertech re-reads your newly modified PCM , that way the flash file it stores internally matches your new base settings)
As for the lack of replies... several probably opened the post and then just closed it as your original post is kind of hard to read (puncuation and paragraphs would make it easier)
As for why you're hitting the rev limiter or why the speedo is off... you need to verify that what you entered into edit is correct... tire height and rear gear ratio...
Also would be helpful if you could post what you set the RPM and MPH limits to in the WOT shift tables...
I'd try setting your MPH at:
28 for 1>2
56 for 2>3
96 for 3>4
(Yes, the MPH's are lower than actuals -- 3>4 should actually occur around 118 MPH. This was assuming you have a 25" tire BTW.)
and set your shift RPM at:
6100 for 1>2 (motor spins fast in 1st w/ 4.10's)
6200 for 2>3
6200 for 3>4
Also, don't trust the tire height calculators. Get a tape measure or a yard stick and find out what the height really is. My 275/40/17's were really 25 inches - not the 25.66 inches that the calculator said. Given you're running 4.10's with a 6600 RPM rev limiter, that's probably a good place to start. Do a couple WOT runs and make your adjustments.
28 for 1>2
56 for 2>3
96 for 3>4
(Yes, the MPH's are lower than actuals -- 3>4 should actually occur around 118 MPH. This was assuming you have a 25" tire BTW.)
and set your shift RPM at:
6100 for 1>2 (motor spins fast in 1st w/ 4.10's)
6200 for 2>3
6200 for 3>4
Also, don't trust the tire height calculators. Get a tape measure or a yard stick and find out what the height really is. My 275/40/17's were really 25 inches - not the 25.66 inches that the calculator said. Given you're running 4.10's with a 6600 RPM rev limiter, that's probably a good place to start. Do a couple WOT runs and make your adjustments.
Last edited by SSpdDmon; Aug 31, 2005 at 03:58 PM.
ok, sorry about that guys, im have just gotten overly frustrated.
i had it set at:
29mph and 6300 in 1st
64mph and 6300 in 2nd
left 3-4 factory at 155mph and 6300 (need to drop speed i know)
i could not figure out why it hit rev limit in 2-3 set here but i can see now that i should lower mph and rpm to take into consideration the time it takes for it to think and intiate. we did shorten its initiating time or how ever you say it.
thanks for your help
i had it set at:
29mph and 6300 in 1st
64mph and 6300 in 2nd
left 3-4 factory at 155mph and 6300 (need to drop speed i know)
i could not figure out why it hit rev limit in 2-3 set here but i can see now that i should lower mph and rpm to take into consideration the time it takes for it to think and intiate. we did shorten its initiating time or how ever you say it.
thanks for your help
