4L60E gbox problems!!!! slow gear change

[Efi_Ls1_Rail]

I am crew to a efi ls1 drag car, we've been pestered with the continuing problem of a slow gear change. originally it was 1>2 and 2>3 we tried everything in our tuning programs and nothing! eventually we swapped the computers with a new one and BAM! 2>3 is fine now.. still 1>2 continues to ping out majorly before gear change. we have talked to other tuners and nothing.

any help would be greatly appreciated.

thanks

 

[FL_Rob]

Without knowing your current mods,I would say valve body re-calibration.
Did you modify the 1-2 servo? Several A-M builders have them for
not too much. Is it flare-ing at all? I mean solid shifts-just at the wrong time/ too late shifts? Is there good [ressure?

 

[Efi_Ls1_Rail]

It's pretty much stock standard besides a lumpier cam which was installed when the ls1/4l60e set up was in the commodore and worked fine. Since being placed in the rail it just hits the limiter, Grrr we got told it was a "laggy computer" something to do with the circuits??? but yeah.. we're bust for idea, i will talk to driver tomorrow and get more info.

 

[FL_Rob]

Youre really running out of gear too soon,due to lower total weight,sounds like.Changing overall/final ratio (rear diff). or a manual valve body kit
would give total driver control at the track,still allowing automatic mode other times.Try talking with the tech guys at TCI or B&M ,,if only to extract information

 

[Efi_Ls1_Rail]

cheers will give that a shot