@FORZDA3 I'm going E85 with full exhaust, whipple FMIC, aFe intake, HPFP w/injectors. Adam from ZFG estimates I'll have ~550 awhp, I have the diffy stiffy as well I picked it up without even realizing the subframe issue just to add support for pushing close to double the crank power. No I don't race on weekends or go to the drag strip frequently I would just hate to get on the road and break down on the way to pick up the wife and kids, or something extremely inconvenient Would you replace the subframe or you think the diffy stiffy will save me the hassle?