[s-cars] power loss question

[Elijahallen92 at aol.com]

Hi,
 I have been thinking about getting the car on a dyno soon and am not sure 
what rpm they start at but if I am in forth gear and start at say 2000 rpm's, I 
floor it, the car gets to 3000 or so and builds boost, by 3500 I'm at full 
boost but right after I hit full boost power cuts way off and boost drops. Its 
not a violent shut off like overboost where it feels like you just left the 
tranny in the road but more like if you went from full throttle to half throttle. 
The only time it does it is if I floor it from a very low rpm like that which 
is never but I am worried that on the dyno I will have a problem with this. 
Any Idea what/ why this happens? Thanks,

Elijah