When side mounting a round tank like that it is a better idea to tilt the tank a bit forward so the outlet is more rearward. On a hard launch and a partially full tank, the fuel is pushed back and up in the tank. With the tank outlet pointed forward or down, the fuel pump could be sucking air. Easy to loose a race that way unless you
Always make sure the tank if full before you race. Just my opinion, others will vary.
Side story. I drag race cars now and then and have seen guys chase out of the hole bog or stumble problems. They would only keep a couple gallons of gas in their tanks to "save weight". Well when they launch, there wasn't any fuel for the fuel pick up to suck. You can only help smart people, stupid people stay stupid... Telling them they are running out of gas doesn't seem to click. No problem for me
I'll just make a clean run with sufficient fuel and win the race. Also they needed jet extension tubes on their secondary carb jets to keep the jets in the fuel but like I said, you can't tell stupid people anything as they know better...