b-series valve springs and retainers

Does anyone know high I can rev my b20vtec using Portflow b-series valve springs and retainers? I have a b20 vtec in a 92 HB with Y-21 tranny (SIR II/Del Sol Vtec tranny), CTR cams, JE 10.8:1 compression pistons, mild ported and polished head, 3 angle valve job, P28 Mugen chipped ECU. I was using the CTR valve springs and retainers, but my girl blew the motor when she was racing my car. According to the machine shop, she bent 4 valves. She downshifted to 3rd when we were already going about 90-100 mph.

i wouldnt rev over 8200rpm or so