timing advance

Fellow classics, my 454 falls on its face at higher rpms. Running quadrajet carb. Cleaned, new cap wires plugs etc. timing set at 8*. im scratching my head as to what it could be. any pointers. fires up quick idles and runs great. So i dont know. thank you!

I'm looking at purchasing a 2001 Sundancer 340 with the 7.4MPI engines. The survey uncovered that the starboard engine was not putting out the same RPM as the port engine - 3900 vs. 4400. The current owner has been diligent (through a certified marine mechanic) but unsuccessful in resolving...

i hope you guys can help me out with this one. i have a 84 gm 305 motor with an edelbrock 1409 carb. my carb was backfiring alot so i started playing with the timing. i keeped advanceing it slightly till it stopped backfiring but i couldnt get to stop completely. i am no expert on motors but i...