Dodge says that the 6.1 should run on 91 octane. You could try 93 octane to see if there is any difference in performance.

 

i use 93 because where i live 91 is not an option. I have used 92 and 91 before when on a road trip because that was their premium grade. I didn't notice any difference at all. I believe its because if you put somethin higher than 91, the computer has to adjust the timing to go back to 91

 

I think you would be wasting your money really. The car is programmed to run on 91 octane. It would be like putting premium fuel in a camry, whats the point? No advantage unless the timing is programmed for the higher octane

 

Unless you have a tuner, higher octane is a waste of $$$$$

Even with the tuner @ 93, I tried mixing 93 (2 gallons) & 100 (5 gallons) with no improvement in ET's

Use GOOD gas! About every 6k I drop injector cleaner in the tank. Probably a waste of $$$$ but it makes me feel better.

 

Thats right on key Goody, use GOOD FUEL not high octane fuel. Big difference. I also use the injector cleaner every so often. I think it will help in the long run, no short term gains though.

 

Chevron makes a great fuel injector cleaner always look for the word tech-tron.This stuff actually works unlike some of the main stream brands at don't dissolve the gunk as fast .

 

i use lucas myself, it seems to be very good stuff.

 

I tried to run higher octane in my magnum Rt and it only ran worse.
Run what they spec for the car only this isnt like the old days when you could by airplane fuel to run on.
The 5.7 doesnt like K& n drop in filters either as I ran into issue with the car missing when I installed a K&N drop in.

 

yep, higher octane doesnt meant its better or cleaner. Its just a different mix, and with our computers, you need the right mix

 

Thanks everyone! Just wanted some feedback. Here in WY since we are above 5000 ft we get 85, 87, 89, & 91 grades. Thin air gets by with less.

But I used to live in SoCal and had a super charged GS Regal. I worked for GM for 15 years even though I have drive a Dodge since I was 15, well owner my 1st Dodge at 13 but could not legally drive. (Dont old that aginst me, they broke more so I had a lot of work)

Anyway on the GS I re-programed the EE PROM and installed an adjustable sensor to modify the waste gate pressure. Stock it ran 8-10lbs boost on 93 oct full load of course and once it heard any rattle the boost and the timing get kicked back along with fuel curve modifications. I experiamented with 100 OCT UniCal Nascar fuel at that time and with the mods it would run between 13-15.5 lbs boost depending on driving conditions, weather etc. Even at steady speeds of 70 on the freeway I would get about 1.5 better fuel MPG, but it did not offset the price. But did run about .5 sec faster i nthe 1/4 with the fuel and the mods.

Just thought that maybe the 6.1 would maybe advance the ignition & fuel curve with better fuel?

That said you guys are correct, without enough compression higher OCT can actually make less power if lack of compresssion combustion design etc do not exist.

Anyway this is a new engine for me and never owner one, so I know little about how they behave.

thanks again everyone!
:SM127:

 

On your stock 6.1, even withs heads, cams, headers and all bolt ons. It will run best with normal premium (91-93) We have tried race fuel, 100, 106/108,111,116 octane and see no hp gain in the race fuels on a stock compression engine. If you buy a forged engine with higher compression or run a turbo/supercharger, then you can tune the car for more boost and create more power. The only reason to run above 93 is to avoid detonation commonly caused by forced induction.

So please always run the recommended fuel from the factory. If it says premium, run premium. Yes the car will still run on 87, but the computer will be pulling power and you will loose efficiency- probaly resulting in less MPG

 

Oh yeah! Tim is the man in the know! Thanks.

I also try not to get any fuel with ethanol. I think it hurts performance.

Any thoughts Tim?

 

thanks Tim for the explanation details!

 

Don't put that crap in your car, save your money and use quality 93 from a branded station .

 

I've used 93 in my SRT-6, didn't notice any difference from 92/91, but CAM 2 was a different story , you put that in and it's pretty noticeable, but ridiculously expensive.

 

Ethanol has its advantages and disadvantages. This debate can go on for pages, but a super quick break down.

Negatives:
It has less stored energy then gasoline. Diesel fuel has even more then gas. What that means is that you will get less MPG and produce less HP with ethanol. -- Its a fact.

Ethanol also absorbs water easily and is more corrosive to non-flex fuel vehicles. Flex fuel cars have different fuel systems then the regular model.

Positives:
It cost less

We then send money to American farmers rather then countries that may not like us too much.

It has a much high octane then gas. This is only benificial if you have a forced induction engine or a very high compression ratio. So even though it makes less power per given volume, you can Crank up the boost and, in the end actually make as much or more power then regular gas. Example: You want to run 20psi on your engine. Probably not going to happen on pump gas. You could, (in theory) run E85 at those boost levels and make a ton of power.


Summary: I wouldnt worry about running a blended fuel like 99% of gas stations in the US have. But depending on what state you live in, if you pick a fuel that has less ethonal, your car may make more power. --- You just may not be able to actually feel it.

Also there are websites out there that show you where different companies buy their crude. I often try to pick BP because they buy less from middle eastern countries and more form other parts of the world. ---- No offence to our Middle Eastern friends. We Power Ported Performance, ship Thousands of dollars of parts to our Arab re-sellers monthly and they are very cool guys who love Dodges, Chryslers and the HEMI.

 

Tim,

The Arabs are the ones with inexpensive fuel and no emmissions testing....I would do tons of marheting there!

Thanks for confirming my thoughts on the ethanol issue.....I know my Charger didn't like it. Come to think of it, my last STS caddy didn't like it either!

 

Racing gas supplement (TORCO) will but it is pricey..

 

Higher octane actually slows the burn but does not give you more power. It allows you to use a higher compression without detonation (ping). That's why high performance engines usually use high test gasoline.

In most street engines, you should run the LOWEST octane you can and still not ping. If you can not tell if the engine is pinging, then use what the manufacturer recomends.

 

On 10.5 compression late model hemi engines, our testing has shown that 100 Octane 100% pump gas will allow on average the car to take 4 degrees more timing as compared to the average 93 pump gas with a 6 to 8% ethanol mix. On a stock engine at 360 to 370 rwhp you're getting somewhere in the range of 3 to 5 horsepower to the wheels, on a 426 up at 500rwhp or higher we can't even make 10 horsepower. With custom tuning, we race on 100 octane but for just hitting the track for testing or for fun, we usually splash a gallon of 100 octane on top of 4 gallons of 93 when we race for the most economical mix.

Joshua

 

Thanks for all the input and feedback guys.

I guess what I was looking into was if it would help with even a stock engine in terms of spark advance etc, and on a custom tune. For me to understand how the computer would be able to advance the spark faster etc, and maybe a little more total to optimize performance. I have many years of GM experiance designed the ECMs and EEPROMS for years and they were so far ahead of Dodge, Ford etc. Not that I am a GM guy, I only worked for them becuase supply demand, more work more $$ etc. Always been a Dodge guy since I was 14, now 48.

Anyway:
One of the advantages in todays engines with a computer on board is that we are able to run decent compression, ya has a lot to do with the head design, pistone design, material too etc, but the computer and spark control are so fast you get away with crappy fuel and a hot engine. Hell on a non computer car you needed 93 regular leaded gas on an 8.5 engine. 100 + on 10.5 and up.

I just know I used to have factory rep leased Regals , one a Grand Nation turbo intercooler etc.. loved as good as gas as you could get.

The other was a GS with a super charger. I modified the waste gate sensor the PC curve etc as was able on 92 to load 9 lbs of boost, and on 100 octane 15lbs of boost. This was done on the proving grounds for the GNX and other input testing on the 231's back in the 80s and 90s.

So it looks like from everything said on a stock internal 6.1 even with basic mods, tuned PC etc that super unleaded is just fine. I was just thinking it may run a little better if it was n the 95 octane or so range.

But I hear ya on everything else too, higher octane without enough sqeeze, timing fuel etc is waster money and can even make less power since it is harded to burn or should I say a controlled explosion.

I just have no base line on these newer 6.1s and that was my initial reson to the forum to get info from those that have been there done that.

thanks everyone! :SM127: