I have just about everything that can be done to my 94 ECSB Z71.
I have a .040 bore, rebuilt 906 vortec truck heads, vortec tbi intake, mellings MTC-1 cam, tuned by Ed Wright, stock replacement dizzy and coil, Taylor 8mm wires, and AC Delco plugs. I have a TBI spacer, ported TBI from Roy Morse, stock 350 injectors, 18psi fuel pressure spring and a 155lph pump from Brian Harris. I’m also running an open element top and side K&N filter. Exhaust is summit racing ceramic shorty headers, true duals into Jones Full Boar 10 series mufflers (knock off flowmaster 10’s) into 18” echo chambers.
All of that is pushed through a NV4500 transmission with a ceramic clutch, and this was after destroying two NV3500’s. I’m also running a 6 lug 14 bolt with 3.73’s, but I’m lacking a locker to transfer the power to both wheels.
I plan on regearing to 4.10’s and a Detroit whenever the cash becomes available. The estimated power/ torque is in the neighborhood of 375/380 (figure is conservative at that), but it is a wild ride for something that weighs close to 6k pounds. Mine was built for towing and play, I have not had it on a dyno to verify power, it is only speculation.