while working on this I wanted to get an idea as to how long I should set the time delay I got my daughter to give the system a manual test getting her to disconnect the choke supply voltage and driving for a couple of minutes then pulling over and hooking up the choke supply than continuing to drive - what we found is that it didn't really make any noticeable difference. I've decided the project isntbgoingbto help in its current form. I'm thinking of reworking things and just making a data logger and making recording some temperature readings and work out a better solution - maybe some way of opening and closing the cooling flaps in the fan housing would be a better way to go