Cameron,
Thank you,it is the ex Peter Voigt,Ken Macmaster ,Richard Homer,Russ Ward car and I don't want to mess around with it too much.
Two of my pals run another G17 and a Vixen,both Imp engines and both downdraught carbs without any problems so that would be the answer,but there is so much history with the car that I don't really want to change it.
But I may extend the inlet manifold to take the carbs away from the heat.A winter time job.
Lister