I just had a Whipple 2.9 installed on my 2009 GT500. I have had two different tuners to put a tune in the car; however after both tunes, the car bogs when cold during the shift from secon to third, third, to fourth, etc. It bogs/stumbles for a couple of seconds and then runs smoothly. Does anyone know what causes this problem and how to fix it?

Secondly, after I drive it and get it to normal operating temperature and let it sit for about 30 - one hour, it is very slow about starting. It just so happens that I don't drive it that much (currently 2300 miles), and this generally happens when I am attending a car show and a crowd of people are around it.

The car has the following:

* JLT cold air induction
* Cobra Jet Throttle body
* American Racing long tube headers, X pipe, and high flow cats
* Mafia
* AFCO dual pass dual fan heat exchanger
* One piece aluminum derive shaft
* Lower pulley
* Of course a Whipple 2.9

The first tune was put in the car by Second Street Speed in Perkasie, PA. The second tune was put in the car by Springfield Motorsport in Lorton, VA. Any assistance that someone can give me will be very much appreciated.

Thanks