performance tune with 89 octane gas?

[flyntgr]

Could I, or could a CMR tuner, install a performance tune, leaning out the a/f ratio and adding spark to increase h.p. I have a 185 degree thermostat and mopar CAI, but all other mechanicals are intact. Reggie

[fordomatic69]

Yup. I'm doing it right now. I am running 89 Octane with the 91 CAI tune. I pulled 3* of timing and increased the shift firmness only and have had 0 knock ever since. I log for knock at least once a week and so far, nothing!

[flyntgr]

fordomatic, it's good to learn you've come over to the Rebellion side. Thanks for pioneering the 89 octane setting. Have you timed your car in the 0-60 or quarter mile to see what differences there are with this program? Have you seen any drop off of gas mileage? I think the cars run better with higher octane, and get better mileage, so that it's not really a10 cents per gallon disadvantage. What do you think?

[mdck1965]

What are your tune settings with the 87/89 octane? I used to run 93 and got real good mileage, but with the crunch on, I would like to get what the sticker said on my car when I bought it. 17 city 25 highway. How is one to attain that with the lower octane fuel. I don't have EVIC, so I have to wait to fill up. I have put a few more pounds in the tires and try real hard to let the MDS stay engaged unless somebody tries my patience. Has anyone tried and succesfully found the happy medium between power and gas mileage, or should I take the 91 CAI performance tune off and restore the original? If somebody has a list of the settings they use, I would love to experiment. Thank you for your time.