can anyone help me im having a couple of problems with my SR20det engine. I have put racing pistons and rods in it after the old ones blew around the rings. it went fine, then the fuel pump went so I swapped it for a 550hp fuel pump, but now the engine is losing power when you plant your foot. I cant find any air leaks from the turbo as it felt like the same thing when i lost a hose from the turbo to the inlet manifold, I have re-tuned it and it still losses power but when i take the vacuum hose off from the return line on the fuel rail, it seems to get back some power but not as good as it should be. two Questions ,Will the engine need to be remapped for the bigger fuel pump? and what is the dial on the back of the ECU for ? Any help on this is greatly apriciated