The title describes it all... when I am boosting at 5k + RPM's I can get a faint smell of coolant in the cabin. Maybe it is just my imagination, maybe it's not... I have a keen nose for funny smells that do not belong though!

What are your thoughts on this?

I replaced my spark plugs this afternoon because I was getting ignition breakup... the first turbo would kick in fine but I was having issues with the secondary turbo spooling up --- the new spark plugs helped with the ignition break up and this car pulls like a champ now.

 

I would check your turbo coolant hoses, I had the same issue. It ended up mine had a crack in it and would leak small amounts of coolant which would burn off instantly since its so hot down there. There is a write up on http://www.rx7.org/Robinette on how to replace.