The other day I had a run with my other car AM vantage v8. My brother was driving it and we started the race from zero. I spanked him

. The second run, my other brother was driving it. He has a good shifting technique. We start (by this time my clutch start to be hot) head to head until I shifted to 4th, he started to gain very slowly. When we shifted to 5th, my brother couldn’t shift properly and I gained 2 cars by then. I must say that our beast amazes me every time. (///M loyal person)
Here is a question. Does the clutch have anything to do with being a little weak on 4th gear? If yes, then I think when it is cold, I would win the race.
If he could shift properly I think he would win the race.
PS: My both cars are stock.
Another PS: My clutch could not handle a 3rd run since it started slipping

.