ticking /knocking/dieseling sound at beginning of throttle/engine noise

[SR20drftSX]

whenever ive driving and this is in every gear , the first half inch into the throttle and after i let out after i push in the throttle more it makes this noise...its very loud when i have the hood up and using the manual underhood throttle on the throttle body , it sounds like metal hitting metal , i recently switvched from 93-87 octane fuel , idk if its knocking or what...i dont here this sound when its ideling tho , only when its like an inch or less into the throttle , when im maintaing a constant speed , not accelrating or deccelerating...thanks alot in adavance...also i would like to BUY a DOHC motor...need to retire the ole SOHC i think...thanks alot guys...(and gals)

Garrett H , NY