Well Ed, I'm pretty new at this and I've learned a lot from your other posts throughout this forum. Thanks for that. But, respectfully, I'll keep running my 15%. It seems to run fine with it and I'm not one to fly wide open with it anyway. Regardless of what nitro fuel you run, it seems that, in this situation, boex just needs a little more fiddling with the fine tuning on his engine.

Boex,
As for 15% being a must, I wouldn't go that far. The reason I've got a 2300 today, along with my OS and Saito engines, is because I wanted to find out FOR MYSELF whether these ST engines were any good. If they were, they are one of the best kept secrets in the hobby, if not, at least I'd know for myself. Well, I think the guys who are doing so much complaining about them are actually ST afficianadoes, that are just trying to discourage others and keep the price down for themselves.

I'd say it's not a must (and I don't think its contributing to the problem you mention here) but if you get the chance, try it, you may like it!