So after reading these posts about the DSP I ordered on from Moe's yesterday. My question is that all of the gas stations where I live (Alaska) have different octane amounts than what the tuner has settings for. The only octane amounts that the stations here have are 85, 88.5, and 90. With this should I use gas with higher or lower ratings for any given tuner settings? I did try doing a search first before posting but did not find an answer to this. I am really looking forward to getting the tuner as this will be my first performance mod. Hopefully budget will allow for other mods soon that will take more advantage of this tuners capabilities.

 

Without an octane booster, I think you will be stuck using the 87 tune. Do not use fuel rated lower than what the tune requires. So if you have 85 in now do not use any of the tunes, if you have 88 or 90 you can use the 87. May want to go onto diablos website and see what they say about it, or try to find some octane booster and see if it works.

 

Thanks for the advice. I was thinking that it would be better to go with higher octane gas rather than lower than the tuner setting. I will check with Diablo as well.

 

Hi all!
Just finished reading this thread and I' seriously thinking in buying one for my ride.
I'm quite happy with the performance of my Durango, but if I can had an extra punch for a few $$, why not?
The petrol in this part of the world is very cheap, the only problem are the temperatures. Also, your petrol should be different from ours here. We only have available 91RON and 95RON.

Cheers!
Ricardo

 

My recommendation to both of you, or anyone reading this in the same situation is to do what truckin151 said and run the lower octane first. Once You've got everything loaded, try logging for knock and see what you get. I'd have to say that's the only way to know for sure.

 

Well, do ypu know how the 91RON or 95RON compare to our octane levels? I am not sure if your 91 is like what our 91 is so you need to check that out.

Just DO NOT run any gas with a lower octane level than the tune you are programming requires. If you are loading the 87 tune DO NOT use anything lower than the 87 rated gas, if you are running the 91 tune DO NOT use anything lower than 91 rated gas, if you are running the 93 tune DO NOT run anything lower than 93 rated gas. The programmers reduce timing or add timing to depending on the tune and you can do some serious damage if you run an octane less than what the tune requires.

 

I've googled a bit and found the following:

In Europe 98-octane gasoline is common and in Japan even 100-octane is readily available at the pumps, but this octane nomenclature is misleading to Americans as foreign octane ratings are derived entirely differently from our own... So, like every other measurement system it seems that everyone else uses a different scale than we do, but unlike most other instances where we have had the good sense to create different units of measure in this case we all use the same name...
Japan and Europe use a system called RON or Research Octane Number to determine the octane rating of their gasoline, while stateside we use a system called AKI or Anti-Knock Index to determine gasoline's octane rating... Interestingly, to further complicate things it would seem that our own AKI system is actually derived from the average of the RON system and another more complicated system referred to as MON or Motor Octane Number... So, to recap our methodologies for measuring gasoline's octane rating are different, but share some common elements...
So, with the commonality of RON in mind a good rule of thumb is as follows, multiply the foreign RON Octane rating by 0.95 and you will have the US AKI equivalent.

( RON Octane Rating x 0.95 = AKI Octane Rating )
98 RON Octane x 0.95 = 93.1 AKI Octane (US measure)
100 RON Octane x 0.95 = 95 AKI Octane (US measure)

So, as you can see the 93 or 94 octane fuel we are all paying an arm and a leg for is actually quite comparable to the higher octane fuels found in Europe and Japan. The people whom have to worry about low octane rating are our friends out west in places like California that are subjected to substandard 91 octane.
91 AKI Octane (US measure) = 95.5 RON Octane

 

That's good info! Too bad it has to be so difficult... They should make it a standard, like "SAE" or is SAE only in the USA? I dunno... thanks for the research. I'm sure some others will find it useful.

 

what better for the 07 diablo or SC thinking of going back to a tunner in the new rig?

 

for an 07 with basic mods go with the sc after they get the trans stuff updated.