alternative to timing retard during shift

A forum for discussing applications and implementations of the MegaShift transmission controller code for the GPIO from B&G. This can control up to 8-speeds and 6 shift solenoids (plus a 16x9 table for controlling a PWM line pressure valve). It has manual and fully automatic modes (16x9 load x speed table), with under and over rev-limit protection, and full data logging of all inputs and outputs (among many other abilities). A TransStim to test your completed board is also available.
Post Reply
ca434sbc4
Posts: 8
Joined: Sun Sep 14, 2008 8:43 pm

alternative to timing retard during shift

Post by ca434sbc4 »

Lance,

Did you ever make any progress on finding an alternative to timing retard for turbo app's?

Having the boost spike during a shift is not the best for the trans. I tore up a full billet built 4l70 last year. 4L80e going in soon.
Matt Cramer
Posts: 55
Joined: Thu Apr 17, 2008 5:19 am

Re: alternative to timing retard during shift

Post by Matt Cramer »

This almost seems like an anti-lag in reverse...

Some possible ideas that come to mind are reducing torque by opening the wastegate further, opening a blowoff valve to dump boost, or grab a BMW ASC valve (basically a drive by wire throttle that is normally open, with the ECU closing it - the unit is put in series with a cable operated throttle body) and have it closed while shifting.
Post Reply