So new to me, with the car I have now and NHRA rules as they are can't run standard antifreeze in the motor. I went with a race coolant from Summit Racing (it's blue). Says on the bottle do not mix with regular anti-freeze. I live in Ohio, and garage isn't heated so for winter this stuff needs to come out. I put pet-cocks on both sides of the block. I had planned on draining all this coolant out and putting in regular anti-freeze just for the winter. But with the do not mix warning on the bottle, now I'm second guessing that without a major flushing of the system. What all are you guys doing to store for winter? Just draining it empty? Storing with anti-freeze?

Since you have petcocks on the block I would drain and catch it so you can reuse it, I seen its $28 a gallon.... Flush the system out with water and fill with 50/50 antifreeze.

Repeat in the spring and put the blue back in.

I question just how detrimental it would be to mix regular antifreeze with it. Probably wouldn't hurt anything but at $28 a gallon I am running it through a filter and saving it.

Can you drain the expensive Blue stuff and save it? If so just leave the system empty for the winter and refill with the saved fluid next season.

I can drain it, and plan to save it yes. Just wasn't quite sure if it would all come out or be stuck in some pockets somewhere and cause an issue. I had planned for what the previous reply mentioned, to drain, flush, fill and then repeat in the spring. Just wasn't to sure on the mixing being that I'm sure there will be some little bits left somewhere. The stuff is a little different, it stains white when it gets on painted surfaces.

"Blue stuff" sounds like Evans, which supposedly doesn't freeze.
On my car (sig pic), even though it always lived in a heated shop, our power occasionally goes out in winter.
I've always just drained its water & Water Wetter (block drains & radiator) and never had an issue.
Water expands when it freezes, but if there's air in the system, I don't think it'll crack anything.
Another alternative is a block heater, or external heat.

I have not done this but I heard the idea of using RV antifreeze!

They said it has less residue and easier to remove in the spring/ I am concerned as one way to lower the freezing point is to simply add salt to the water

Has anyone done this?

i wouldn't add salt !!!
as i live where salt brine and plain salt is used on the roads in the wintertime, i would be very concerned using salt would cause severe corrosion issues inside the engine.
cars rust severely here due to the salt used, and i would think the engine water jackets, aluminum water pumps, and radiators of any construction, would be no different.

I know anti freeze is hard to clean up and some tracks ban its use, but I can't find it in the NHRA rulebook where it isn't allowed. Am I missing something? Every year that there is a hard prolonged freeze down here, you hear about some racer that damaged a block because they didn't get the plain water out of their engine. It is difficult to get it completely drained. I think NHRA knows this happens, and would be a reason to not have an outright ban.

One track I run at have it in their rules for a certain ET and quicker can't run normal antifreeze.

I would drain both the radiator and block, both sides, and let it sit for the winter. I would pull all the spark plugs and squirt oil into the cylinders and then spin the motor over with the plugs out and then put the plugs back in and make sure to not start again until you put the coolant back in the motor

Mine sees -30F possible. As mentioned, I drain race water solution and both sides of the block. Make sure to remove the petcocks, to ensure the block fully drains. I have heard of the possibility of corrosion obstructing the petcock near the end of the drain, holding water behind it and then freezing. I then store with 50-50 glycol.

Bingo