Time for a new converter?

[wmerrell]

On the drag strip the boost is jumps from 20 lbs to 23 lbs when the transmission automatically shifts into 3rd gear.

Is this a tranny problem or converter problem?

Converter is a 2800 restalled D5.

Is it time to call Dusty?

 

[mikestertwo]

Is this a tranny problem or converter problem?

Neither. It's caused by the increased load on the motor.

 

[youngstr]

I thought the opposite is supposed to happen when the car shifts?

Neither. It's caused by the increased load on the motor.

Thats wierd, when mine shifts at wide open I loose a pound or two, I always figured it was because the rpms where droping off on the shift and my turbine was slowing down with the dropoff in rpms. I've never gained boost on a shift though.

 

[Dusty Bradford]

Your D5 will do a great job of pulling in 3rd gear. A higher stall would help spool-up and 60' times. You most likely have a wastegate issue. Did you port the hole in the housing to match the puck size of your downpipe?

Like has been mentioned. It's the increased load causing the boost to raise. If the wastegate hole isn't enlarged the issue will be more drastic.

 

[Dusty Bradford]

Thats wierd, when mine shifts at wide open I loose a pound or two, I always figured it was because the rpms where droping off on the shift and my turbine was slowing down with the dropoff in rpms. I've never gained boost on a shift though.

If you have excessive rpm drop, this can cause what your seeing. The other issue is the factory wastegate system. It's not known for it's rock solid boost control.