slight idle surge and throttle cutting out on downshift

[marshallrule]

hey guys good morning,
I am a major noob to computer tuning, so after buying my hptuners setup I took my car to a very reputable shop for dyno tuning. the car is an 09 challenger rt with a 392 stroker 3.927 bore 4.050 stroke it has a custom comp cam from modern muscle 228@50 .602 and 238@50 .597 on a 114ls heads are hand ported stock eagles and it has a 6.1 intake with a 90mm tb, i don't know how much of that you need but there it is...
The car made 439hp and 452fl/lb at the rear wheels and it drives ok but if I try to downshift the 6speed manual I loose throttle until it gets back to around 1000rpm then the throttle comes back like nothing ever happened also the idle intermittently surges at stop lights (one it will the next it wont)? any help would be much appreciated.

andrei tune plus 2.hpt

[Homer]

I not a pro tuner but your tune has me wondering a couple of things.

So you have no throttle response when you downshift? Does it happen immediately after downshift or if you are off the throttle for a few seconds? Wonder if DFCO is kicking in and not turning off on when throttle is request? In VCM scanner, do you have an option to add throttle torque source? This will let you know if your request for throttle is being acknowledged by the PCM or if torque management is taking over.

Considering you have significant mods to the engine I am also wondering why the tuner chose not to enable sensed MAP, not to mention the engine size was not changed to 6.4 in the tune?

[marshallrule]

I completely agree on the sensed map and the change in displacement but assuming he used a wide band o2 sensor to tune the fa ratio I don't want to change these things and screw the whole thing up.
If i shift to a gear with equal rpm the throttle doesn't have any issues its only if i downshift to a gear that would raise the rpm, ill have to look on the throttle torque source.

[spoolboy]

I completely agree on the sensed map and the change in displacement but assuming he used a wide band o2 sensor to tune the fa ratio I don't want to change these things and screw the whole thing up.
If i shift to a gear with equal rpm the throttle doesn't have any issues its only if i downshift to a gear that would raise the rpm, ill have to look on the throttle torque source.

I hear you loud and clear.

But if the whole VE table is based on bogus information, nothing will be correct except WOT on the dyno where it was tuned.

That explains why your VE table goes well over 100%.