Sniper Classic

I have bought a sniper classic 2007 model ac having twicw valve float my exhaust valve knoked on my piston and smoke is coming out on my pipe im planning to change my block for mx 150 the rest is stock except for rcdi that is installed when i bought the mc do i need to replace the valve spring because it might cause a valve float again im having headache haha pls help what king of set up for mx150 block tnx