Ok I now timing will very. but like I said before we have 3 of these engines and have no trouble with the other 2. this is a brand new race car and we are no stranger to the 2300 4 cylinders. it has a new 6al msd system with a 500 holley with 76 for jets. and like I said before 1 & 4 look like new. we are running around 12.5 to 1 compression.