Here's a dumb question: Would using a higher grade gasoline in a car still running a stock 87 tune affect fuel economy or performance? If not, would there be any advantage at all?
Yep car has been running on E85 since new. Thats regular up in Colorado.If you're tuned for a better fuel though it will make a difference, for example I have a 91 octane tune.
Dustin, let me get the strait, you've put E85 in your car? I'm surprised it even ran and if it was running I would imagine it being way too lean.
It has to do with direct injection, a car cannot detonate if fuel isn't there yet. Plus now with both variable cams you can play with ignition timing a lot more so you don't need gas with reduced volatility.I read the other day that the LAP 2.2 has a compression ratio of 10 to 1. That's pretty high for regular isn't it? I know a lot of people have said use what the manufacturer says, but I don't understand how most cars above 9.5 to 1 usually recommend higher than regular but GM says the 2.2 LAP with 10 to 1 can run on regular.