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What the highest octane level we can run without a tune before the computer starts having issues? Not 93 or 94 octane but 100-105 octane is what I’m specifically asking about.
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Short answer, it will make a ton of power on E30 without any additional tuning. I was shocked how much E30 woke it up.What the highest octane level we can run without a tune before the computer starts having issues? Not 93 or 94 octane but 100-105 octane is what I’m specifically asking about.
I am getting the CRP 53mm stage 3 turbo upgrade done to a second turbo I have sitting in my garage and once someone can crack the ECU and I can get a few tunes to work with the turbo and higher octanes is why I am askingoctane rating is the resistance to burn with the higher the rating the harder to burn. You want to run the lowest octane you can without pre ignition to get the most use/ performance generally.
E fuel above the commonly available E10 or less really should be tuned for the specific mix when needed. E85 has a great octane rating but requires IIRC around 30% more fuel.
Leaded is when things go south as they gum up cats and mess up o2 sensors...I know some guys back in the day used to mix turbo blue with 93 octane on boosted setups just for a little bit of safety when 100 unleaded was not available.
In short 91-93 is probably all we need unless you are really pushing things then you are moving into the specialty E85 and 100+unleaded/leaded tuned setups and at that point you are kinda all in unless you have different tunes for different fuel setups.
What do you define as high compression/high boost with a turbo? The 2.7 already has 10:1 compression (and some 2.7's ran 10.3:1 compression) while still running about 20 psi of boost.93 octane is all you need without higher compression pistons or milling heads to raise compression. Unless you start running over 10 to 1 compression more than 93 octane is a waste of money. High compression and turbocharging are a recipe for disaster. Thats why engines with high turbo boost require lower compression. Same holds true for engines with blowers. High octane fuel is for high compression naturally aspirated engines.
I’m currently have the K&N intake,AFe charge pipes, and mishimoto intercooler. Sending off the turbo for the upgrade and patiently waiting on SPD to make a downpipe for the 2.3 or anyone else for that matter. Had a tuner but got rid of it. I’m trying to learn , hence my question.Generally speaking, 100 octane is more than sufficient for a vehicle without a tune that would ensure no timing retard. There would be no detriment to running other than your wallet.
Turbocharged vehicles benefit greatly with higher octane contrary to the previous message. It depends greatly on the tune and boost target and ramp coupled with the overall compression and timing of the tune. I have ran 105 octane and even leaded mixes (no cats) as well as e85 only tunes in high boost turbo applications for the past 20 years. That said in a completely stock vehicle 93 octane seemingly would be more than capable of hitting all marks on a normal tune.
Citation needed. I was running with with an engine monitor and the engine management had no problem adjusting to E30 and made quite a bit more power.You will receive absolutely no benefit on a stock tune running over 93 pump gas. As a matter of fact, there's an argument to be made that you'd possibly make less power on a higher octane fuel because it is less energy dense, hence its higher resistance to pre-detonation/knock. Do NOT listen to anyone advising you to run higher ethanol content fuels without supporting mods and a tune. Yes, it might technically make a bit more power, but not safely. It takes more ethanol based fuel to maintain a stoichiometric air:fuel ratio than it does with gasoline. "Lean is mean."
I can raise my hand on that as well. 3.6L Porsche with over 1200HP.Citation needed. I was running with with an engine monitor and the engine management had no problem adjusting to E30 and made quite a bit more power.
It wasn't lean, it wasn't even close to lean. That said, I am not advising anyone to do anything regarding E85, that's up to anyone who wants to try it. When I was stuck behind enemy lines in California, the 91 Octane pump gas was absolutely horrible, I used to either go to Willow Springs to gas up or add a few gallons Toulene to bump the octane (both better options than E85, if you want to avoid the pitfalls of Ethanol). One legitimate danger of E85 is the need for more frequent oil changes, that is a fact. You don't want to run E85 and not be on top of maintenance, period.
I did notice that my local gas station is selling unleaded 100 octane sunoco 5 gallon buckets. So maybe I will run her down on fuel, load up the Ford performance tune, and put 5 or 10 gallons of real race gas in the Bronco (which has a higher octane than E85).
Now, who here has made more than 300 HP/liter at the wheel on a turbo engine they tuned?
Rotary engines don't count LOL just kidding I couldn't resistCitation needed. I was running with with an engine monitor and the engine management had no problem adjusting to E30 and made quite a bit more power.
It wasn't lean, it wasn't even close to lean. That said, I am not advising anyone to do anything regarding E85, that's up to anyone who wants to try it. When I was stuck behind enemy lines in California, the 91 Octane pump gas was absolutely horrible, I used to either go to Willow Springs to gas up or add a few gallons Toulene to bump the octane (both better options than E85, if you want to avoid the pitfalls of Ethanol). One legitimate danger of E85 is the need for more frequent oil changes, that is a fact. You don't want to run E85 and not be on top of maintenance, period.
I did notice that my local gas station is selling unleaded 100 octane sunoco 5 gallon buckets. So maybe I will run her down on fuel, load up the Ford performance tune, and put 5 or 10 gallons of real race gas in the Bronco (which has a higher octane than E85).
Now, who here has made more than 300 HP/liter at the wheel on a turbo engine they tuned?