Help My Tt Is Being Foul!!!!

:banghead: I have a 93 R/T TT Awsome car i love it to death - will never get rid of it --- but i was all big headed the one night an decided to race a Z06 Vet :mad: need less to say i lost when he threw it in 6th gear but i kept up until then - i am the second owner of this an old guy had the car b4 me an it was never beaten on or what have you... he had the sexy auto serviced every 2000 miles basically had a tune up done - so it was even get the oil an shit changed even b4 it was due..... he had all the records all the parts on it are orig. i recently replaced the Thermostat/the Water Pump/and the Timing Belt since i had the half the engine apart so i did the belt too cause i would been due probably in another 10k miles..... the car has 387,758 miles on it an it still ran like a champ- i took it to a buddies that has a dyno an it match the stock stats so i was happy it wasnt even a hp or a lb ft off, then i race the damn vet - after i let off the gas i heard a hiss an was like oh shit wtf now ... so i pulled over and checked it seemed that the one turbo was not spooling an holding boost so i had no choice but to puppy it home an it drove fine an ran fine just didnt get on it or anything - then on the way home i almost got hit by a truck running a red light so i punch the gas a lil to get outa the way an as i started to go up a hill i heard another loud his . now neither turbos seemed to be spooling or holding vacume so i parked an let it sit for a few days then tryed to start it an it would barely run - so i am tryin to figure what could be the problem --- could the turbo wastegates be stuck open or something like that - cause that is what i was hoping an thinking it might be...?

Please help
Thanks
Matt