virg -
Welcome to EM! I'm glad you have been "savin' da gas" all these years. I would like to hear about your Volvo 122 experience. I have this eerie feeling I am slowing becoming a pseudo-Corvair/Saturn owner myself. But, I doubt I will be able to keep mine going for 30 years!!!!!!! I'd be ecstatic to just reach 300K miles.
I have a hydrogen generator from
www.hydrogen-boost.com, but I have been too chicken to do all the extra mods needed to make it work as claimed (MAP and 02 sensor, fuel heater). In my opinion, the simplest/ most economical place for it is in diesel engines under "normal" workload. What I mean by "normal" is using the diesel engine under normal non-hypermiling conditions.
CarloSW2