Have you tried starting it w/o this exhaust pipe?
How long and what diameter is this pipe that is venting the exhaust outside? If it were too long/too small it could be causing a great amount of restriction, more than the engine can overcome. Some say even the small exhaust deflectors cause...
I have no first hand experience with the LRP .30X (comp model) or .32, but I have plans for the .30X in the near future in my own truck.
I read that some have had an issue holding a tune with the .32, some don't.
Reviews are generally positive for the .30X and its only rated at like .15 less...