The pressure system eliminates most of these issues. If the change is extreme then its still not the best of solutions but in your case its not an issue.

If the tank was mounted in the tail of the model or maybe out in a wing tip then the possible line loss in the fuel tubing could be an issue....If the tank is within about 12-18" of the engine it is fine and vertical distance is not really an issue within reason as well.

Troy Newman

Team YS