you need to run the engine in for the first 1000miles. use mineral oil from halfords 10w40, start car and hold the revs around 2k, for a like 10 -20mins. go out and do a 10 mile drive, drop the oil to get rid off all the crap thats inside, then do 1 at 100miles, then 250, 500, 750 1000 use 10w4 fully/ or semi this is how i did my forged engine.