fuel additive for winter storage?

[hotz]

Hello everyone, Hope everyone is doing well and enjoying the holidays.
My question today about what fuel additive/stabilizer to all of you use when parking your cars for the winter? I generally don't put 20 miles on my car a year so sometimes the gas can get a little old since the car is sitting. Gas might be a year or two old before it gets used up. I generally use Ethanol free gas and vary on the octane level. What would you recommend to add to the gas tank that will aid in keeping gas good?

This is for a few cars. I have a 1922 touring but also have a 1969 Camaro and 57 Nomad. Would you use the same additive in all of the cars or is there something different thats better for different year cars?

Thanks for the help and look forward to hearing back from you all

[rocco376]

I like Seafoam.  Seems to keep the gas fresh.

[lakeholme]

I have five old cars and a 24 ft boat. I put non ethanol in the prewar cars and boat.  During the winter I use Sta-bil products. Everything starts right back up in the Spring.
I have used Seafoam in the past mainly to clean out carbon deposits and moisture when I first buy an old car.
For two years, thanks to Covid, we didn't run the boat. I really thought the gas would be bad and the fuel injectors would have to be replaced. Thanks to Sta-bil Marine it started right up and ran fine.

[David K]

Sta-bil for Ethanol cars here.

[COPOZ/28]

I have also used Sta-Bil for a few decades with good results.  About 10 years ago, I switched over to the ACES IV stabilizer and octane enhancement product from BND Automotive.  It equals the performance of Sta-Bil when it comes to keeping fuel fresh over long periods of storage.  But the ACES IV product has other other significant advantages over Sta-Bil.  It does a very good job of enhancing the octane level of unleaded gas, something Sta-Bil does not do.  It also reduces ring/bore wear.  Both of these advantages have been documented by Automotive Engineer/Racer/Tech Writer, David Vizard, in extensive A/B dyno tests he has run.

[boomer632]

There is no fuel treatment that will cure or prevent ethanol fuel from evaporating and turning into varnish (sugar) if it sits long term. Its that simple.. there is no product that does it. Solution.. ethanol free if long term storage is expected

[77thor]

Seafoam or Sta-Bil