brundz

who knew? not me...maybe thats why i'm gettin some misses[:@]

92hatchLX

With 14 or more degrees of timing I would suggest 91+ octane. Anything under that will work fine with 85-87 octane unless you're pinging.

Trainman

Mine will only run on 93. Anything else and she pinges a little bit.

brundz

o...damn i wish it was that easy to fix these damn misses. my friend has had 2 capri's 2 mustangs and just did a 5.0 swap on another mustang and he told me they run on premium...but i guess he was wrong. thats surprizing. oh well i do still have to check the timing so hopefully that'll help and maybe if i advance it a little bit it will help more

92hatchLX

stock timing is 10 degrees you should be fine on 85 octane. I'd replace spark plugs, plug wires and your cap and rotor if you haven't done so already. They only run on premium when you've got the timing bumped up enough to have a reason to run premium.

PJB

I just run 87 in mine for now. I havent gotten around to screwing with the timing yet.

93 LX FiveO

+1 same

i ran 93 in her one day just to see what would happen.. nothing

waste of mnoney.. it actually burned faster too

Infantryman

I agree if I use premium gas it runs out faster than the cheap gas.

grabbem88

cap is cracked!...plugs have holes in them.....plug wires are cut in half.................ok a little out there,but check'em

86HOGT

The only legitimate reason to run premium is bumped timing, bumped up compression , and/or BOOST.