So i purchased a 98 t5m s70 a few months ago.

yesterday, i smashed into a parking barrier and cracked my radiator. After replacement, my boost is spiking to 15psi all the way up to 22psi at WOT in 3rd and 4th gear. the engine studders when this happens. If i leave my foot a little light on the throttle i can hold 15psi and the car pulls hard. Why? It would peak at 10-11psi before this happened.

I'm assuming i messed something up when i put the new radiator in.

suggestions? thanks.