well since in the book, it says the hemi should be ran on mid-grade gas.. since gas prices keep climbing it's gettin expensive. i was wondering, does anyone here run their hemi on regular 87 octane gas and not have any problems? like do you get any pinging in your engine or not? i had run my car on regular for awhile before i actually got my book from the dealership, but i did not notice any noises from the engine. so anyone have a bit of help for me? thanks

 

Sask Cruiser,
You will need to get a Mod Chip for your car, then change the settings for the lower octane fuel. Take a look around here in previous posts, that was a popular Mod before the spike in costs. I think the Intake and Exhaust Mods will also help your MPG...

 

i'm not about to buy a chip.. i'd rather just cough up the extra few cents per litre. i'll just stick to using mid grade. since i'ver cut the resonators out i havn't really noticed much difference in gas mileage if any.. i have noticed however that cruising around my car shifts so that i'm revving at like just over 100 rpm.. say at about 40 mph, if i'm going slower it'll still shift to the next gear up so i'm revving at just over 1000 rpm.. i've never noticed this before i took the resonators out. but i ended up taking my cone filter off and put the stock intake back on for now lol. damn filter started to fall out of the intake tube and i was too lazy to make something up to make it work properly.. took it back and got mt money back that i needed more lol

 

i have been running regular in my RT since about the 3rd tank. I have had my car 3 1/2 years and have had no problems. I lost about a mile per gallon when they started diluting it with ethanol. I think in normal driving you will be ok. If you are going to drive it like you stole it all the time, then buy the higher octane.

 

I've been running 87 octane in my '05 R/T since I bought it without problem or loss of mileage. You don't need a mod chip.

=M=

 

I have a2005 R/T and the manual says use "regular unleaded". That's 87 octane.

 

the higher the gas prices, the more of a bargan the mid grade is. when gas was $0.79 a gallon mid grade was $0.89
now, when gas is $4.29 a gallon, mid grade is only $4.39. do the math, it is the greatest bargan out there.

 

you might want to look in your owners manual again. the 5.7 hemi and the 3.5HO both require 89 octane.
the 6.1 hemi requires 91+ octane.

 

I have run 87 octane in mine forever. I have noticed no noises or problems. I know many people who do the same.

I get an average of 21 mpg, and as high as 24 - 25 on the highway.

I do run a fuel injector cleaner through the tank at each oil change.

No problems for me.

 

I have 07 rt and I tried 87 for a couple tanks and mine started pinging bad. I run 89 now and I still get the normal hemi clickety clak