what grade of gas is recommended for a r/t charger

OK, lets open that can of worms again...

My 2006 Daytona R/T recommends 87 octane in the users manual. It will run fine on regular gas. If you add a Superchips programmer, or another brand, they have the option of tuning your engine for more power with a premium gas setting, either 91 or 93 octane depending on where you live (some people can only find 91 octane).

Things to consider:
Regular gas has a greater energy density, than premium gas. It potentially can get better mileage, and more power per gallon.

Premium gas has additives that help keep injectors clean, and octane boosters to allow the engine to develop more peak horsepower, if the programming takes advantage of it. If you run the stock program, regular gas may actually run your car to lower ET's.

In heavily congested areas like Houston, where I live, the gas has two different formulas for the same grade of gas during the year. From about October to April, we get normal gas, just like everyone else. But from April to October we get an "oxygenated blend" that reduces vaporization, and emissions on hot days. The net result is a gas with significantly lower energy density. If you ran a 1/4 mile with the winter blend, and all other environmental factors were the same (ie temperature & humidity), it would be 2/10 to 4/10 quicker than with the summer blend of gas. That sucks. When I go to the track I go with an empty tank and buy 2 or 3 gallons of 107 octane. The octane does not net any additional horsepower for my engine, but it does not have the oxygenating crap, which gives it a much higher power density, more zoom, zoom, zoom (sorry Mazda).

Overall geographic location, driving style, and engine programming should guide you in choosing the correct fuel grade, if your wallet doesn't....

Thats weird cause my R/T's manual says to run 89octane for best performance. If you are modified with a chip and the basic bolt-on's then I suggest to run 91 or better yet if you have it 93octane. If you have really crack your engine open and added a cam and performance heads then 93 is a most and if you throw in 100octane you'll probably see alittle more HP.

i run 93 all the time in my 2.7

The 2006 Charger Owner's Manual says to use 89 octane for the 5.7L HEMI.

Sorry, my mistake. It still runs fine on 87....

i'll probally put the 91 when i get mine

since i bought my R/T back in august i have used nothing but SUNOCO 93 octane in it

seems it gets a little less mpg then what i have read (10.4/city per evic) but have not had any problems so far

i DO plan on using the diablo along with a 180 thermostat when the weather gets nicer

persoanlly i dont think it can hurt the car using 93, just hurt the wallet :D

I run all of them fine,but it does call out 89

I havea 2006SE PP w/3.5 engine. I tried running 87 in it and got a check engine light, mis-fire on cyclinders. I switched back to 89/93 octane and the CLI went away. What's anyone opinion on what to use to get good gas mileage since the cost of gas is going up?

at today's gasoline prices
and spread between regular and 93 octane premium
it may be that premium that HAS NO ADDED ETHANOL
might give a cost effective MPG increase

your tax $ paid for this EPA study of how
regular grade 87 octance gasoline heat content varies across the USA

http://www.epa.gov/orcdizux/rfgecon.htm

notice gasoline varies from 108,500 to 117,000 btu per gallon
so your MPG will be expected to vary about 9% too

The Bosch Automotive Handbook lists typical regular gasoline at
113,000
and premium gas at
118,000

toulene 126,650 (Formular One racecars used this when tank limit rules were in)

iso-octane 110,342 (100 Octane 'laboratory standard' gasoline is this pure chemical)

ethanol 75,900

acetone 80,700

if you buy yourself a digital scale
and weigh either exactly one gallon or one liter
the gasoline that weighs the most per volume (density)
usually has the most btu/gallon

your state's agriculture department may test gasoline
and if so will usually do one test per year for you
on octane and heat content
if you ask nicely

Standard Labs or Commercial Lab company
will do a commercial test for you for about $100 per test

The EPA claims a difference of 1.7% BTU/gal ... My instrumented results paint a far bleaker picture. I get far more than a 1.7% improvement with the winter blend here in Houston...

Toluene seemed like such a good idea, until I read the health risks associated with it.