need help so bad!
 

i just bought my 93 rx7 twin turbo. the problem now is. i decided to replace the 1" hose in my engine with a smaller diameter hose. like 1 level smaller.and then i test drove her and all of a sudden i heard 2 popping sound in coming from my engine bay and my car stalled. she was able to start back up but always stalls.now shes having bad idle. and every time i step on my brake and put pressure on it she stalls.i dont know what could be the problem.i put back the old 1" hose and still stalls.need help please! thanks!:confused::(