PREDATOR-Z

Here is the deal:

I have a Level 5 tranny with a VIG 3800. Under juice it doesn't want to shift 2>3 and hit rev limiter. Even if I shut off the N2O it will delay.

I spoke to Chuck from FLT and he suggested it could be a tuning issue. He said that the pcm has to see the RPM and MPH to shift.
Tranny has less than 2Kmiles on it and 12 passes.
1>2 OK
2>3 Hittting limiter
3>4 OK

I've tried lowering shiftpoints but no help.

Could anyone point me in the right direction. I have HPT.

Thanks a lot
Mark

jay_99z

iTrader: (5)

If you lowered both the RPM and MPH shiftpoints I'd say it's a trans problem and not tuning. Especially if it shifted OK when first installed.

performabuilt

iTrader: (25)

We it could be a tuning issue but question you didnt say, did it do this from the begining with this trans stall combo? or did it happen after being driven for a while and if so how long .
And remember also its my understanding as Im not tuner that you have to lower both the shift MPH and RPM together.

PREDATOR-Z

No it did this from begining, not a trans problem, it has the best of everything. It does that under extrem load (juice).
I think I understand what is the issue. My MPH is too high, so the pcm is seing RPM shift commmend but doesn't take action since the MPH parameter is not reached yet.

Time for some test and tune

performabuilt

iTrader: (25)

I would agree then if it did it from the begining then its likley a tuning issue from what I have noted reading through the forums it can be quite tricky

PREDATOR-Z

Just as an update,

Chuck, performabilt and others were right.

Did some tuning and tranny performed flawlessly yesterday at the track.

Thanks to every one for the help.
Much appreciated.
Mark

FLT

iTrader: (1)

Mark,

Glad to here you got it figured out.

performabuilt

iTrader: (25)

Yes glad you got it solved , Many times the trans wether a new built unit or a stocker can get the blame for and issue , But everyone should bear in mind that with the newer elecronic 4l60e/4l60e etc that there are many things outside the trans that can affect performance, The 4L60E can only do what its told. I allways tell people when you have and upshift or downshift issue the first thing to do after checking codes is to if you have the capability which most tuning software and most any quality scanner can , Look at what the PCM is commanding. If its not telling the trans to shift then it wont. Also note that using the software to comand the shift is not the same thing.You must observe that the pcm actually made the command , Not that you told the PCM to make it. Even when I have used the snapon scanner in command mode to tell the trans what gear to be in I have noted it will not overide the PCM programing.
But again glad you got it solved

FLT

iTrader: (1)

Reasons just like this is why FLT owns a dyno. It truly helps us rule out a lot of problems if the customer has a one. Glad to hear you got the tune dialed in. Now you have to get the trophy again this season. Vince