yea, im not sure what compression ratio my car has, but i have to put 93 octane in it, i was just trying to figure out rougly what it might be around
thakns
Like mustang70 said, usually around 10:1, but this isn't always the case. I have seen cars with 11.5:1 that run 87 and cars with 9:1 that needed 91. If you have a set of heads that have quencher chambers, then you will be able to run a lower octane then a motor whose heads don't have quencher chambers. Timing will also be a factor along with air/fuel will also play a minor roll.