For all of the guys with FLP, or other trannies that use a vacuum mod. kit. What needs to be done to the PCM tune in order for everything to function properly with transmission shifting properties? Will certain trouble codes need to be eliminated? I know that the vacuum modulation kit controls line pressure, so will that pcm table need to be modified?

Please post any information you know... Thanks.

 

ttt...

 

You don't have to change the tuning. The pcm will still control the tranny when driving under normal conditions. Vhe vacuum takes over when drive it hard. Just make sure you have a check valve on the vacuum line going to the tranny.

 

The vacuum controls the line pressures only,the rest is still controlled by thr PCM.You adjust the shift points and converter lockup.

 

what does that do?

 

Some of us have found out the hard way that the PCM reduces transmission line pressure to soften shifts to protect the transmission's weak components and that reducing line pressures on a really powerful engine combo can easily fry clutch packs resulting in transmission failures.When vacuum modulation is used part throttle shifts can be soft,but the line pressures are maintained at full throttle,to take full advantage of the increased engine power and reenforced transmission components.A check valve is added to the vacuum line on boosted applications to keep positive pressure out the vacuum modulator.