Which is proper fuel needed????

[steve128h]

I have an 08 charger R/T with CAI, and some aftermarked exahust, although i dont know which one it is because i bought it like that already, but its loud. I have the predator with 93 CAI tune and im wondering if I should run the 91 CAI tune is it safe to run right now in the winter with 93 still in the tank and will it really make much of a difference? also if this car is met to bet best at 89 gas, then why run higher fuel? Does it really make much of a difference?? Please help educate me.

[brandy16]

The 93 cai tune advances the timing so you need to run 93 oct gas or you will have alot of knock. Most of us take the tune out over the winter. The tunes cut back on traction control,add timing, and add fuel with the cai tune. If the weather is good in the winter where you live leave the tune in. You can also get a winter tune from one of the guys at diablo just aske them

[09SuperBee]

You're running 89 in an RT? Doesn't it say right in the gas door 91 or better? I just hate to see someone mess up a Hemi.

[Mike_Levy]

Nah, 5.7s are designed to be run on 89 when stock. The 6.1s have higher compression, which is why we need 91/93.