551 since no one else has taken that. It's just a shame that you are limiting the build with 91.
If you still have the PCV valve and the system hooked up thats most likely what it is. Esp if you wernt running any oil seperators.
I want to see what the pump gas numbers will be. Dont worry, Ill be doing e85 full time when its no longer a daily driver. Ill post up some e85 dyno numbers when that happens.