I'm having an issue where the coolant is rising to the top of the expansion tank on track. It looks like its a common issue with the 270 and 310 because they don't have the radiator bleed hose to the expansion tank that was fitted to the earlier Sigma-engined cars. My car is a 2020 310R with the later radiator too, so there's no room to lower it to fit the common return hose mod either.
Has anyone fitted a water swirl pot to solve the same problem? Do people fit these to Caterham race cars?