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91/93 octane query


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Alright guys, I may be in a bit of a bind. I am driving from WI to CO and I have only come across 91 octane. I have a 93 octane Cryotune currently. I don't have a 91 octane map so what are my options? Octane booster-do they really raise it enough? If so what brand or will any 1 do the trick.

I do have my AP with me so I could retard the timing ("You never go full retard!" Lol). Anyway I just don't want to blow my car up on the trip so any help would be appreciated.

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Octane booster is a joke. If you read the back of the bottle it tells you it only raaises it by tenths of a point in mostcases. That's as good as doing nothing. If you retard timing a bit and don't go WOT all over the place youll be fine.
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The ecu normally will but he hdoesnt have stock enginemanagement.he has a tune he said so the computer is forced into different parameters. Itt wont react quite the same as stock. Willi t adjust some?yes. But not as much as ifot were stock managementm. as far as being in cothe fuel trims will go down a bit because the air is thinner. Soi in a sense its getting "less air" so it will time down a bit accordingly. I'd retard timing a bit. In co I'd say higher octane would be better because the higher the octane the longer the burn time. (That's the diff between 87-93 and why u can have more timing with higher octane because it will burn for that extra amount of time your asking it to by igniting it sooner) so a higher octane in a lower oxygen level environment would probably help get the most out of everything.
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Two summers ago I drove from Michigan to Colorado and back. Total trip was around 3000 miles when all was said and done. Once I got out of the states where 93 was available I threw a bottle of STP octane booster in with each fill-up. I was periodically checking the learning views and never had any strange fuel trims or learned knock in any of the cells. I wasn't exactly driving it gingerly in the mountains either.

 

Engine did not blow up. Did the additive help? I don't know. Certainly didn't hurt anything. Only negative is a few extra bucks at each fill-up. Post-trip Blackstone report showed no issues other than elevated levels of manganese, which is one of the ingredients in the STP product so not really surprising. The next oil change dropped back to zero for that element. 133,000 miles today and the oil analysis I just did came back great.

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My car was tuned on 96 octane gas, and ran 30k miles on a variety of Costco's cheapest 92 and somewhat better 91/93. It even had a tank of 87 (Oregon's gas jockey rule). Put in the octane booster every tank if it makes you feel better. If you are going to running it hard, find a station that sells race gas and add that.

 

Lastly, if your engine is so finely tuned that 2 octane points are going to kill it, it's time to find a new tune.

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The only reason I said he may want to change something is because of his outspoken concern, and I've seen what can happen when you put too low of an octane in a car tuned for higherr. Granted that was 87 used and driven "hard" on a 93 tune but still.
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The ecu normally will but he hdoesnt have stock enginemanagement.he has a tune he said so the computer is forced into different parameters. Itt wont react quite the same as stock. Willi t adjust some?yes. But not as much as ifot were stock managementm. as far as being in cothe fuel trims will go down a bit because the air is thinner. Soi in a sense its getting "less air" so it will time down a bit accordingly. I'd retard timing a bit. In co I'd say higher octane would be better because the higher the octane the longer the burn time. (That's the diff between 87-93 and why u can have more timing with higher octane because it will burn for that extra amount of time your asking it to by igniting it sooner) so a higher octane in a lower oxygen level environment would probably help get the most out of everything.

 

What he's trying to say here is that the stock tune will compensate for 'bad gas' --ie, an owner who puts in 87 instead of 91/92/93. To the driver, this will feel like reduced performance due to timing being retarded as much as it possibly can.

 

Aftermarket tunes, such as Cryo, or Cobb, will tune the ECU to 'ignore' certain things, such as an EGT input where one does not exist, or TGV motors. Something that will likely remain untouched, or even enhanced, would be reaction to knock events.

 

I'm sure Cryo follows a standard of pulling timing at a knock event (real or perceived), such as can be caused by gas with the improper or insufficient octane rating; pulling timing, gradually putting it back, until the knock stops, or a new knock event is recorded.

 

So while it does not technically have the 'stock' knock control, I would wager that any aftermarket tune, such as Cryo's, or Cobb's, would mimic the stock params for such events, or, perhaps even be better.

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I wasn't too terribly concerned about the whole situation given most of the mileage was hwy cruising. I haven't really taken it out of state before. I hadn't realized how prevalent 93 is in WI yet tough to find as you go west.

 

Made it to Denver safe and sound. Thanks for the reassurance. I only ask cuz she's so damn temperamental. Might bump into Dave from Cryo if time permits. If anyone has any local must see's let me know

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I wasn't too terribly concerned about the whole situation given most of the mileage was hwy cruising. I haven't really taken it out of state before. I hadn't realized how prevalent 93 is in WI yet tough to find as you go west.

 

Made it to Denver safe and sound. Thanks for the reassurance. I only ask cuz she's so damn temperamental. Might bump into Dave from Cryo if time permits. If anyone has any local must see's let me know

 

Given your octane fears, I'd make "bumping into Dave from Cryo" a priority. :eek:

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I got a tank of gas at a sketchy looking gas station on my drive between CA and WA as I was low on gas and it was the best option available. By the end of that tank I pulled a learning view and it had pulled a lot of timing for the "91" that I had gotten but then the next tank in OR where I made sure the gas jockey put in 92 the ecu put back all the timing it had pulled. All of this was done on Dave's tune so I wouldn't be too worried about it.

2005 Vader Wagon

Material Tests on Ringland Failure Piston

I should have held off and purchased a wagon instead of the spec.B
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I actually spoke with Dave a bit ago. Its all good nothing to worry about. He's a great guy and it was nice to finally put a face to the man behind my HP. Picked up a t shirt too. He was tuning kgrizzlys Spec B on the dyno. New built motor, hta71... looked like nothing but fun.
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