4.6L Stroker Choice Fuel 87,89,91 Octane

I was wondering for you guys that have the 4.6L Stroker what grade of gas are you using. My compression ratio on my stroker is 9.5.1
and I was using 87 octane. I have been having a misfire at idle and at low rpm and I have looked, tested and replaced almost everything. Guys could it be the 87 octane, do these motors pre ignight the fuel due to the higher compression and cause it to misfire. Today a filled up with 91 octane to see if it would make a difference. It is a little too early to tell because I still had 1\2 a tank of 87. What do you guys think of this.

a trick i like to use that some old guy taugh me was to put lead additive in the tamk makes your octane rating go way up and lubes the top end and fuel pump pretty good

I don't have a stroker yet, but I have been re-searching. I had a conversation with the guys at Golen Engines, and was told that they recommend "premium fuel" only due to the higher compression ratio. I do know that my stock 96' det./pre-ig. really bad on 87, I'm running 93 only now, and getting better mpg.

My 4.6 stroker has a CR of 9.3:1 and is ping free on 91 octane (95 RON), the lowest grade of fuel available in the UAE (the other grade is 94 octane or 98 RON).
Since you have 1/2 a tank of 87 and 1/2 a tank of 91, you effectively have a full tank of 89. It might make things a little better but don't hold your breath.

I run 9.4 to 1 with no issues, but I have a Renix which can back the timing off if there is pre-dsetonation present. Quench height is important for keeping detonation in check, if you got it right, it can really help fight hot spots that can lead to pre-det.