I decided to do some testing for myself. I took a new DuBro black gas stopper fresh from the package, and soaked it in my K-1/2380 mixture from my fuel can. After 3 hours it looks like that in the photo. Unfortunatly, within the first 30 mins of soaking it was already deforming. I need to go to the Hobby shop and buy the brown stoppers, and others intended for gas, diesel, and Kero for soak testing. I'll post my findings. I've done a search on RCU regarding this subject with little results.

I'm not sure what brand to use in my jet now. Am I doing something wrong here?

Thanks,
Chris