I have been running a 50/50 e85/98 ron tune for months now. I already had a pw surge tank and 60lb dekkas, but the rest of the fuel system is stock. so essentially it cost me a jerry can of e85 and the cost of the tune to change to ethanol. power increase is excellent as it can cope with extra timing which in an xr6t means ALOT of extra power. mine is held back a little though as the ba rods are not up to the task as much as later model ones, so that limited the amount of timing the tuner would dial in, just for safety. the down side for me is the closest place I can get it from is 45mins away. so whenever im going to town I take 7 jerry cans and fill em all. with a 50/50 mix it lasts 6 tank fulls, so not too bad... I also reccomend running e85, just have a 98 tune in the flash so if it is not available, your not inconvenienced. enjoy!