For what it's worth, I run a bottle of Techron from my Chevron full service gas station through the SRT-4 every 6 months or so. If you read the write-up about Techron on Google, it's about the ONLY additive that is recommended for gas unless you want to add the AMSOIL gasoline additive, P1.

These are not octane "boosters", but engine fuel system and intake valve cleaners.....

Techron works, I don't have an opinion on P1 yet......

 

I use Exxon premium - 91 rated here in AL. I figure, if it is good enough for the Alaskan coastline, it's good enough for my cars!

Stainz

 

an SRT-4 in icy Alaska...now thats an image