How much slower is your lap time with a full tank of gas on a 100% race? I do 50% race distance in my career and while running P1 last night at Silverstone i decided to fill up (52 laps of fuel) and see the lap time difference (this is the first time i have done this). I was astonished to see a lap time 7.5 seconds slower! The car felt like a brick and was near impossible to turn and slow down. I have never felt the car like that at the start of a race and am wondering if i should have only filled up half way? I have read that 1 lap of fuel adds up to a tenth of a second per lap (sometimes it's a bit less). That said, 52 laps of fuel should add about 5.2 seconds to the lap time not 7.5 In my season so far i notice i am usually btwn 3-4 seconds a lap slower at the start of the race. If i start running 100% race distance should i expect to be 7-8 seconds a lap slower at the start?